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+                    GNU AFFERO GENERAL PUBLIC LICENSE
+                       Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+                            Preamble
+
+  The GNU Affero General Public License is a free, copyleft license for
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+
+  16. Limitation of Liability.
+
+  IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR CONVEYS
+THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES, INCLUDING ANY
+GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT OF THE
+USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
+DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
+PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS),
+EVEN IF SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF
+SUCH DAMAGES.
+
+  17. Interpretation of Sections 15 and 16.
+
+  If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+                     END OF TERMS AND CONDITIONS
+
+            How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU Affero General Public License for more details.
+
+    You should have received a copy of the GNU Affero General Public License
+    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+  If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source.  For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code.  There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+  You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.
diff --git a/mod/group_alias/actions/groups/edit.php b/mod/group_alias/actions/groups/edit.php
new file mode 100644
index 000000000..8588cf3ed
--- /dev/null
+++ b/mod/group_alias/actions/groups/edit.php
@@ -0,0 +1,247 @@
+<?php
+/**
+ * Elgg groups plugin edit action.
+ *
+ * @package ElggGroups
+ */
+
+// Load configuration
+global $CONFIG;
+
+elgg_make_sticky_form('groups');
+
+$group_guid = (int)get_input('group_guid');
+$new_group_flag = ($group_guid == 0);
+
+if ($new_group_flag && elgg_get_plugin_setting('limited_groups', 'groups') == 'yes'
+	&& !elgg_is_admin_logged_in()) {
+	
+	register_error(elgg_echo("groups:cantcreate"));
+	forward(REFERER);
+}
+
+$sticky_alias = ('no' == elgg_get_plugin_setting('changeable_group_alias', 'group_alias'));
+
+/**
+ * wrapper for recursive array walk decoding
+ */
+function profile_array_decoder(&$v) {
+	$v = html_entity_decode($v, ENT_COMPAT, 'UTF-8');
+}
+
+// Get group fields
+$input = array();
+foreach ($CONFIG->group as $shortname => $valuetype) {
+	// another work around for Elgg's encoding problems: #561, #1963
+	$input[$shortname] = get_input($shortname);
+	if (is_array($input[$shortname])) {
+		array_walk_recursive($input[$shortname], 'profile_array_decoder');
+	} else {
+		$input[$shortname] = html_entity_decode($input[$shortname], ENT_COMPAT, 'UTF-8');
+	}
+
+	if ($valuetype == 'tags') {
+		$input[$shortname] = string_to_tag_array($input[$shortname]);
+	}
+	
+	if ($shortname == 'alias' && ($new_group_flag || !$sticky_alias)) {
+		elgg_load_library('elgg:group_alias');
+		try {
+			group_alias_validate($input['alias']);
+			$existing_group = get_group_from_group_alias($input['alias']);
+			if ($existing_group && $existing_group->guid != get_input('group_guid')) {
+				throw new Exception(elgg_echo('groups:alias:already_taken'));
+			}
+		} catch(Exception $e) {
+			register_error($e->getMessage());
+			forward(REFERER);
+		}
+	}
+
+}
+
+$input['name'] = get_input('name');
+$input['name'] = html_entity_decode($input['name'], ENT_COMPAT, 'UTF-8');
+
+$user = elgg_get_logged_in_user_entity();
+
+$group = new ElggGroup($group_guid); // load if present, if not create a new group
+if (($group_guid) && (!$group->canEdit())) {
+	register_error(elgg_echo("groups:cantedit"));
+
+	forward(REFERER);
+}
+
+// Keep existing alias unless explicit update
+if ($input['alias'] == $group->alias || (!$new_group_flag && $sticky_alias)) {
+	unset($input['alias']);
+}
+
+// Assume we can edit or this is a new group
+if (sizeof($input) > 0) {
+	foreach($input as $shortname => $value) {
+		$group->$shortname = $value;
+	}
+}
+
+// Validate create
+if (!$group->name) {
+	register_error(elgg_echo("groups:notitle"));
+
+	forward(REFERER);
+}
+
+
+// Set group tool options
+if (isset($CONFIG->group_tool_options)) {
+	foreach ($CONFIG->group_tool_options as $group_option) {
+		$group_option_toggle_name = $group_option->name . "_enable";
+		if ($group_option->default_on) {
+			$group_option_default_value = 'yes';
+		} else {
+			$group_option_default_value = 'no';
+		}
+		$group->$group_option_toggle_name = get_input($group_option_toggle_name, $group_option_default_value);
+	}
+}
+
+// Group membership - should these be treated with same constants as access permissions?
+switch (get_input('membership')) {
+	case ACCESS_PUBLIC:
+		$group->membership = ACCESS_PUBLIC;
+		break;
+	default:
+		$group->membership = ACCESS_PRIVATE;
+}
+
+if ($new_group_flag) {
+	$group->access_id = ACCESS_PUBLIC;
+}
+
+$owner_guid    = (int) get_input('owner_guid');
+$loggedin_guid = elgg_get_logged_in_user_guid();
+$is_admin      = elgg_is_admin_logged_in();
+
+if (!$new_group_flag && $owner_guid && $owner_guid != $group->owner_guid) {
+	if($group->isMember($owner_guid) && ($group->owner_guid == $loggedin_guid || $is_admin)) {
+		$old_owner_guid = $group->owner_guid;
+		$group->owner_guid = $owner_guid;
+		
+		// @todo Remove this when #4683 fixed
+		$owner_changed_flag = true;
+		$old_icontime = $group->icontime; 
+	}
+}
+
+$group->save();
+
+// group saved so clear sticky form
+elgg_clear_sticky_form('groups');
+
+// Invisible group support
+// @todo this requires save to be called to create the acl for the group. This
+// is an odd requirement and should be removed. Either the acl creation happens
+// in the action or the visibility moves to a plugin hook
+if (elgg_get_plugin_setting('hidden_groups', 'groups') == 'yes') {
+	$visibility = (int)get_input('vis', '', false);
+	if ($visibility != ACCESS_PUBLIC && $visibility != ACCESS_LOGGED_IN) {
+		$visibility = $group->group_acl;
+	}
+
+	if ($group->access_id != $visibility) {
+		$group->access_id = $visibility;
+	}
+}
+
+$group->save();
+
+// group creator needs to be member of new group and river entry created
+if ($new_group_flag) {
+	elgg_set_page_owner_guid($group->guid);
+	$group->join($user);
+	add_to_river('river/group/create', 'create', $user->guid, $group->guid, $group->access_id);
+}
+
+// Now see if we have a file icon
+if ((isset($_FILES['icon'])) && (substr_count($_FILES['icon']['type'],'image/'))) {
+
+	$icon_sizes = elgg_get_config('icon_sizes');
+
+	$prefix = "groups/" . $group->guid;
+
+	$filehandler = new ElggFile();
+	$filehandler->owner_guid = $group->owner_guid;
+	$filehandler->setFilename($prefix . ".jpg");
+	$filehandler->open("write");
+	$filehandler->write(get_uploaded_file('icon'));
+	$filehandler->close();
+
+	$thumbtiny = get_resized_image_from_existing_file($filehandler->getFilenameOnFilestore(), $icon_sizes['tiny']['w'], $icon_sizes['tiny']['h'], $icon_sizes['tiny']['square']);
+	$thumbsmall = get_resized_image_from_existing_file($filehandler->getFilenameOnFilestore(), $icon_sizes['small']['w'], $icon_sizes['small']['h'], $icon_sizes['small']['square']);
+	$thumbmedium = get_resized_image_from_existing_file($filehandler->getFilenameOnFilestore(), $icon_sizes['medium']['w'], $icon_sizes['medium']['h'], $icon_sizes['medium']['square']);
+	$thumblarge = get_resized_image_from_existing_file($filehandler->getFilenameOnFilestore(), $icon_sizes['large']['w'], $icon_sizes['large']['h'], $icon_sizes['large']['square']);
+	if ($thumbtiny) {
+
+		$thumb = new ElggFile();
+		$thumb->owner_guid = $group->owner_guid;
+		$thumb->setMimeType('image/jpeg');
+
+		$thumb->setFilename($prefix."tiny.jpg");
+		$thumb->open("write");
+		$thumb->write($thumbtiny);
+		$thumb->close();
+
+		$thumb->setFilename($prefix."small.jpg");
+		$thumb->open("write");
+		$thumb->write($thumbsmall);
+		$thumb->close();
+
+		$thumb->setFilename($prefix."medium.jpg");
+		$thumb->open("write");
+		$thumb->write($thumbmedium);
+		$thumb->close();
+
+		$thumb->setFilename($prefix."large.jpg");
+		$thumb->open("write");
+		$thumb->write($thumblarge);
+		$thumb->close();
+
+		$group->icontime = time();
+	}
+
+	if ($owner_changed_flag && $old_icontime) { // @todo Remove this when #4683 fixed
+		
+		$filehandler = new ElggFile();
+		$filehandler->setFilename('groups');
+
+		$filehandler->owner_guid = $old_owner_guid;
+		$old_path = $filehandler->getFilenameOnFilestore();
+
+		$sizes = array('', 'tiny', 'small', 'medium', 'large');
+
+		foreach($sizes as $size) {
+			unlink("$old_path/{$group_guid}{$size}.jpg");
+		}
+	}
+
+} elseif ($owner_changed_flag && $old_icontime) { // @todo Remove this when #4683 fixed
+
+	$filehandler = new ElggFile();
+	$filehandler->setFilename('groups');
+
+	$filehandler->owner_guid = $old_owner_guid;
+	$old_path = $filehandler->getFilenameOnFilestore();
+
+	$filehandler->owner_guid = $group->owner_guid;
+	$new_path = $filehandler->getFilenameOnFilestore();
+
+	$sizes = array('', 'tiny', 'small', 'medium', 'large');
+
+	foreach ($sizes as $size) {
+		rename("$old_path/{$group_guid}{$size}.jpg", "$new_path/{$group_guid}{$size}.jpg");
+	}
+}
+
+system_message(elgg_echo("groups:saved"));
+
+forward($group->getUrl());
diff --git a/mod/group_alias/activate.php b/mod/group_alias/activate.php
new file mode 100644
index 000000000..630e0362a
--- /dev/null
+++ b/mod/group_alias/activate.php
@@ -0,0 +1,30 @@
+<?php
+/**
+ * Group Alias activation script
+ * It sets an alias if group hasn't.
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+foreach(elgg_get_entities(array('type' => 'group')) as $group){
+	group_alias_update_from_name($group);
+}
diff --git a/mod/group_alias/languages/ca.php b/mod/group_alias/languages/ca.php
new file mode 100644
index 000000000..7639f654b
--- /dev/null
+++ b/mod/group_alias/languages/ca.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * GroupAlias -- Translation strings for Catalan
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+$language = array (
+	'groups:alias' => 'Àlies del grup',
+	'groups:alias:already_taken' => 'Aquest àlies de grup ja apunta a un altre grup',
+	'groups:alias:registration:usernametooshort' => "L'àlies del grup ha de tenir menys de %u caràcters.",
+	'groups:alias:registration:usernametoolong' => "L'àlies del grup és massa llarg. Com a màxim pot tenir %u caràcters.",
+	'groups:alias:registration:invalidchars' => "Perdona, l'àlies del grup conté el caràcter %s que és invàlid. Els caràcters sigüents són invàlids: %s",
+	'groups:alias:registration:invalidctrlchars' => "Perdona, l'àlies del grup conté caràcteres de control, o invisibles.",
+	'groups:alias:changeable' => "Permetre canviar l'àlies d'un grup?",
+	'groups:alias:changeable:may_break_urls' => "Atenció: això pot portar a URL trencats quan l'àlies està ben establert.",
+
+);
+
+add_translation('ca', $language);
diff --git a/mod/group_alias/languages/en.php b/mod/group_alias/languages/en.php
new file mode 100644
index 000000000..4045566e8
--- /dev/null
+++ b/mod/group_alias/languages/en.php
@@ -0,0 +1,42 @@
+<?php
+/**
+ * GroupAlias -- Translation strings for English
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+$language = array(
+
+	/**
+	 * Menu items and titles
+	 */
+	'groups:alias' => "Group alias",
+	'groups:alias:already_taken' => "This group alias is already pointing to another group",
+	'groups:alias:registration:usernametooshort' => 'Group alias must be a minimum of %u characters long.',
+	'groups:alias:registration:usernametoolong' => "Group alias is too long. It can have a maximum of %u characters.",
+	'groups:alias:registration:invalidchars' => "Sorry, your group alias contains the character %s which is invalid. The following characters are invalid: %s",
+	'groups:alias:registration:invalidctrlchars' => "Sorry, your group alias contains control or non-printable characters.",
+	'groups:alias:changeable' => "Allow changing a group's alias?",
+	'groups:alias:changeable:may_break_urls' => 'Warning: this can lead to broken URLs when the alias is well-established.',
+);
+
+add_translation('en', $language);
diff --git a/mod/group_alias/languages/es.php b/mod/group_alias/languages/es.php
new file mode 100644
index 000000000..bf29223e4
--- /dev/null
+++ b/mod/group_alias/languages/es.php
@@ -0,0 +1,37 @@
+<?php
+/**
+ * GroupAlias -- Translation strings for Spanish
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+$language = array (
+	'groups:alias' => 'Alias del grupo',
+	'groups:alias:already_taken' => 'El alias del grupo ya está cogido',
+	'groups:alias:registration:usernametooshort' => 'El alias del grupo debe tener menos de %u carácteres.',
+	'groups:alias:registration:usernametoolong' => "El alias del grupo es demasiado largo. Como máximo puede tener %u carácteres.",
+	'groups:alias:registration:invalidchars' => "Perdona, el alias del grupo contiene el carácter %s que es inválido. Los carácteres siguientes son inválidos: %s",
+	'groups:alias:registration:invalidctrlchars' => "Perdona, el alias del grupo contiene carácteres de control, o invisibles.",
+	'groups:alias:changeable' => "Permitir cambiar el alias de un grupo",
+	'groups:alias:changeable:may_break_urls' => 'Advertencia: esto puede llevar a URLs rotos cuando el alias está bien establecido.',
+);
+
+add_translation('es', $language);
diff --git a/mod/group_alias/languages/fr.php b/mod/group_alias/languages/fr.php
new file mode 100644
index 000000000..54c3f837a
--- /dev/null
+++ b/mod/group_alias/languages/fr.php
@@ -0,0 +1,39 @@
+<?php
+/**
+ * GroupAlias -- Translation strings for French
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+$language = array (
+	'groups:alias' => 'Alias du groupe',
+	'groups:alias:already_taken' => 'Cet alias est déjà utilisé par un autre groupe',
+	'groups:alias:registration:usernametooshort' => "L'alias du groupe doit compter au-moins %u caractères.",
+	'groups:alias:registration:usernametoolong' => "L'alias du groupe est trop long. Il ne doit pas dépasser %u caractères.",
+	'groups:alias:registration:invalidchars' => "Pardon, l'alias du groupe contient le caractère %s qui est invalide. Les caractères suivants sont invalides : %s",
+	'groups:alias:registration:invalidctrlchars' => "Pardon, l'alias du groupe contient des caractères de contrôle ou invisibles.",
+	'groups:alias:changeable' => "Permettre le changement de l'alias d'un groupe ?",
+	'groups:alias:changeable:may_break_urls' => "Attention : cela peut conduire à des URLs invalides lorsque l'alias d'un groupe est déjà bien établi.",
+
+);
+
+add_translation('fr', $language);
diff --git a/mod/group_alias/lib/group_alias.php b/mod/group_alias/lib/group_alias.php
new file mode 100644
index 000000000..eb421e49e
--- /dev/null
+++ b/mod/group_alias/lib/group_alias.php
@@ -0,0 +1,84 @@
+<?php
+/**
+ * GroupAlias -- Shared Library
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * Simple function which ensures that a group alias contains only valid characters.
+ *
+ * This should only permit chars that are valid on the file system as well.
+ *
+ * @param string $alias Group alias
+ *
+ * @return bool
+ * @throws RegistrationException on invalid
+ */
+function group_alias_validate($alias) {
+
+	// Basic, check length
+	$min_length = elgg_get_config('minusername', 4);
+	if (strlen($alias) < $min_length) {
+		$msg = elgg_echo('groups:alias:registration:usernametooshort', array($min_length));
+		throw new RegistrationException($msg);
+	}
+
+	// username in the database has a limit of 128 characters
+	if (strlen($alias) > 128) {
+		$msg = elgg_echo('groups:alias:registration:usernametoolong', array(128));
+		throw new RegistrationException($msg);
+	}
+
+	// Blacklist for bad characters (partially nicked from mediawiki)
+	$blacklist = '/[' .
+		'\x{0080}-\x{009f}' . // iso-8859-1 control chars
+		'\x{00a0}' .          // non-breaking space
+		'\x{2000}-\x{200f}' . // various whitespace
+		'\x{2028}-\x{202f}' . // breaks and control chars
+		'\x{3000}' .          // ideographic space
+		'\x{e000}-\x{f8ff}' . // private use
+		']/u';
+
+	if (
+		preg_match($blacklist, $alias)
+	) {
+		throw new RegistrationException(elgg_echo('groups:alias:registration:invalidctrlchars'));
+	}
+
+	// Belts and braces
+	// @todo Tidy into main unicode
+	//$blacklist2 = '\'/\\"*& ?#%^(){}[]~?<>;|¬`@-+=';
+	$blacklist2 = '\'/\\"*& ?#%^(){}[]~?<>;|¬`=';
+
+	for ($n = 0; $n < strlen($blacklist2); $n++) {
+		if (strpos($alias, $blacklist2[$n]) !== false) {
+			$msg = elgg_echo('groups:alias:registration:invalidchars', array($blacklist2[$n], $blacklist2));
+			$msg = htmlentities($msg, ENT_COMPAT, 'UTF-8');
+			throw new RegistrationException($msg);
+		}
+	}
+
+	$result = true;
+	return elgg_trigger_plugin_hook('group_alias:validate', 'all',
+		array('alias' => $alias), $result);
+}
diff --git a/mod/group_alias/manifest.xml b/mod/group_alias/manifest.xml
new file mode 100644
index 000000000..33bb9bbc2
--- /dev/null
+++ b/mod/group_alias/manifest.xml
@@ -0,0 +1,38 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<plugin_manifest xmlns="http://www.elgg.org/plugin_manifest/1.8">
+	<name>Group Alias</name>
+	<author>Lorea Developers</author>
+	<version>1.8.1</version>
+	<category>lorea</category>
+	<category>groups</category>
+	<category>enhancement</category>
+	<description>Provide clean URLs for groups using an unique alphanumeric identifier.</description>
+	<website>https://lorea.org/plugins/group_alias</website>
+	<bugtracker></bugtracker>
+	<repository>https://gitorious.org/lorea/group_alias</repository>
+	<donations>https://lorea.org/support</donations>
+	<copyright>Copryright 2012,2013 Lorea Faeries &lt;federation@lorea.org&gt;</copyright>
+	<license>GNU Affero General Public License version 3, or later</license>
+	
+	<requires>
+		<type>elgg_release</type>
+		<version>1.8</version>
+	</requires>
+	<requires>
+		<type>plugin</type>
+		<name>groups</name>
+	</requires>
+	<requires>
+		<type>priority</type>
+		<priority>after</priority>
+		<plugin>groups</plugin>
+	</requires>
+	<suggests>
+		<type>plugin</type>
+		<name>linkup</name>
+	</suggests>
+	<suggests>
+		<type>plugin</type>
+		<name>upgrade-tools</name>
+	</suggests>
+</plugin_manifest>
diff --git a/mod/group_alias/start.php b/mod/group_alias/start.php
new file mode 100644
index 000000000..01d4bb080
--- /dev/null
+++ b/mod/group_alias/start.php
@@ -0,0 +1,188 @@
+<?php
+/**
+ * Elgg Group Alias
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ * @homepage       http://lorea.org/plugin/group_alias
+ * @copyright      2011-2012 Lorea Faeries <federation@lorea.org>
+ * @license        COPYING, http://www.gnu.org/licenses/agpl
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This program is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+elgg_register_event_handler('init', 'system', 'group_alias_init');
+
+/**
+ * Initialize the group alias plugin.
+ *
+ */
+function group_alias_init() {
+
+	// Register group alias library
+	$library_path = elgg_get_plugins_path() . 'group_alias/lib/group_alias.php';
+	elgg_register_library('elgg:group_alias', $library_path);
+
+	// Register a page handler, so we can have nice URLs
+	elgg_register_page_handler('g', 'group_alias_page_handler');
+
+	// Override URL handlers for groups
+	elgg_register_entity_url_handler('group', 'all', 'group_alias_url');
+
+	// Add alias field
+	elgg_register_plugin_hook_handler('profile:fields', 'group', 'group_alias_fields_setup');
+
+	// Override groups/edit action
+	$action_base = elgg_get_plugins_path() . 'group_alias/actions/groups';
+	elgg_register_action("groups/edit", "$action_base/edit.php");
+
+	// Extend the main css view
+	elgg_extend_view('css/elgg', 'group_alias/css');
+	elgg_extend_view('js/elgg', 'group_alias/js');
+
+	// Register tests
+	elgg_register_plugin_hook_handler('unit_test', 'system', 'group_alias_test');
+	elgg_register_event_handler('upgrade', 'system', 'group_alias_run_upgrades');
+
+}
+
+function group_alias_run_upgrades() {
+	$upgrade_tools = elgg_get_plugins_path() . 'upgrade-tools/lib/upgrade_tools.php';
+	if (file_exists($upgrade_tools) && include_once($upgrade_tools)) {
+		upgrade_module_run('group_alias');
+	}
+}
+
+
+function group_alias_test($hook, $type, $value, $params) {
+	$value[] = elgg_get_config('pluginspath') . "group_alias/tests/group_alias_test.php";
+	return $value;
+}
+
+function get_group_from_group_alias($alias){
+	return current(elgg_get_entities_from_metadata(array(
+		'type' => 'group',
+		'metadata_name' => 'alias',
+		'metadata_value' => $alias,
+		'limit' => 1,
+	)));
+}
+
+/**
+ * Dispatcher for group alias.
+ * URLs take the form of
+ *  All groups:       g/
+ *  Group profile:    g/<alias>
+ *  Group Tools:      g/<alias>/<handler> => <handler>/group/<guid>
+ *
+ * @param array $page
+ * @return bool
+ */
+function group_alias_page_handler($page) {
+
+	elgg_set_context('groups');
+
+	if (!isset($page[0])) {
+		groups_page_handler(array('all'), 'groups');
+		return true;
+	}
+
+	$group = get_group_from_group_alias(str_replace(' ', '+', urldecode($page[0])));
+
+	if($group && !isset($page[1])){
+		groups_page_handler(array('profile', $group->guid));
+
+	} elseif($group && isset($page[1])) {
+		forward("$page[1]/group/$group->guid");
+
+	} else {
+		return groups_page_handler($page);
+	}
+
+	return true;
+}
+
+function group_alias_fields_setup($hook, $type, $return, $params) {
+	return array_merge($return, array('alias' => 'group_alias'));
+}
+
+function group_alias_from_name($group) {
+
+	$alias = elgg_get_friendly_title($group->name);
+	$alias = preg_replace("/-/", "_", $alias);
+	$alias = urldecode($alias);
+
+	return $alias;
+}
+
+/**
+ * This is an event hook for create/update group to handle the alias
+ * without overriding the groups/edit action.
+ */
+function group_alias_save_hook($event, $type, $entity) {
+
+	$alias_from_name = group_alias_from_name($entity);
+	$aliased_group   = get_group_from_group_alias($alias_from_name);
+
+	// If the alias is already taken by another group, append GUID.
+	if (elgg_instanceof($aliased_group, 'group')
+		&& $aliased_group->guid != $entity->guid) {
+		$entity->set('alias', "$alias_from_name$entity->guid");
+		return TRUE;
+	}
+	// Force keeping default or existing alias if empty or not changeable
+	if (empty($entity->alias) || !elgg_get_config('changeable_group_alias')) {
+		$entity->set('alias', $alias_from_name);
+	}
+
+	return TRUE;
+}
+
+/**
+ * Override the group url
+ *
+ * @param ElggObject $group Group object
+ * @return string
+ */
+function group_alias_url($group) {
+	if(!$group->alias){
+		return groups_url($group);
+	}
+	return "g/$group->alias";
+}
+
+/**
+ * Convert a group name to an alias if it does not exist already.
+ * Return the newly, or existing group alias.
+ *
+ * @param ElggGroup $group Group object
+ * @return string
+ */
+function group_alias_update_from_name($group) {
+	if (!empty($group->alias)) {
+		return $group->alias;
+	}
+	$alias = group_alias_from_name($group);
+	// If alias is taken, append GUID
+	$g = get_group_from_group_alias($alias);
+	if (elgg_instanceof($g, 'group') && $g->guid != $group->guid) {
+		$alias .= $group->guid;
+	}
+	$group->set('alias', $alias);
+
+	return $alias;
+}
diff --git a/mod/group_alias/tests/group_alias_test.php b/mod/group_alias/tests/group_alias_test.php
new file mode 100644
index 000000000..fe33bd69d
--- /dev/null
+++ b/mod/group_alias/tests/group_alias_test.php
@@ -0,0 +1,99 @@
+<?php
+/**
+ * Elgg Group Alias Tests
+ *
+ * Plugin authors: copy this file to your plugin's test directory. Register an Elgg
+ * plugin hook and function similar to:
+ *
+ * elgg_register_plugin_hook_handler('unit_test', 'system', 'my_new_unit_test');
+ *
+ * function my_new_unit_test($hook, $type, $value, $params) {
+ *   $value[] = "path/to/my/unit_test.php";
+ *   return $value;
+ * }
+ *
+ * @package Elgg
+ * @subpackage Test
+ */
+class ElggGroupAliasTest extends ElggCoreUnitTest {
+
+	// New group
+	var $new_group;
+
+	// Saved (aliased) group
+	var $existing_group;
+
+	/**
+	 * Called before each test object.
+	 */
+	public function __construct() {
+		parent::__construct();
+
+		// all __construct() code should come after here
+	}
+
+	/**
+	 * Called before each test method.
+	 */
+	public function setUp() {
+		$this->existing_group = new ElggGroup();
+		$this->existing_group->name = "Aliased Test Group";
+		$this->existing_group->alias = 'aliased_test_group';
+		$this->existing_group->save();
+
+		$this->new_group = new ElggGroup();
+		$this->new_group->name = 'group_alias test group';
+	}
+
+	/**
+	 * Called after each test method.
+	 */
+	public function tearDown() {
+		// do not allow SimpleTest to interpret Elgg notices as exceptions
+		$this->swallowErrors();
+		// Remove created objects
+		$this->existing_group->delete();
+		$this->new_group->delete();
+	}
+
+	/**
+	 * Called after each test object.
+	 */
+	public function __destruct() {
+		// all __destruct() code should go above here
+		parent::__destruct();
+	}
+
+	public function testNewGroupHasNoAlias() {
+		$this->assertNull($this->new_group->alias);
+	}
+
+	public function testGroupAliasSave() {
+		$this->new_group->alias = 'sample_alias';
+		$this->assertTrue($this->new_group->save());
+		$this->assertIdentical('sample_alias', $this->new_group->alias);
+		$this->assertNotNull($this->new_group->alias);
+	}
+
+	public function testGroupAliasUpdate() {
+		$alias = $this->existing_group->alias;
+		$this->assertEqual($alias, 'aliased_test_group');
+		$this->existing_group->set('alias', 'new_alias');
+		$this->assertTrue($this->existing_group->save());
+		$this->assertIdentical($this->existing_group->get('alias'), 'new_alias');
+	}
+
+	public function testGroupAliasPersistence() {
+		$this->existing_group->name = 'Changed Name';
+		$this->assertTrue($this->existing_group->save());
+		$this->assertIdentical($this->existing_group->alias, 'aliased_test_group');
+    }
+
+// @todo: how to tell ElggGroup to save default metadata?
+//	public function testGroupAliasDefault() {
+//		$this->new_group->name = 'A group without an alias';
+//		$this->assertTrue($this->new_group->save());
+//		$this->assertIdentical('a_group_without_an_alias', $this->new_group->alias);
+//	}
+
+}
diff --git a/mod/group_alias/upgrade.php b/mod/group_alias/upgrade.php
new file mode 100644
index 000000000..42b7f794e
--- /dev/null
+++ b/mod/group_alias/upgrade.php
@@ -0,0 +1,37 @@
+<?php
+/**
+ * Upgrade file
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+require_once(dirname(dirname(dirname(__FILE__))) . "/engine/start.php");
+
+admin_gatekeeper();
+set_time_limit(0);
+
+echo "upgrade group alias";
+$previous_access = elgg_set_ignore_access(true);
+group_alias_run_upgrades();
+elgg_set_ignore_access($previous_access);
+
+echo "DONE";
diff --git a/mod/group_alias/upgrades/2012100501.php b/mod/group_alias/upgrades/2012100501.php
new file mode 100644
index 000000000..9deeda2a7
--- /dev/null
+++ b/mod/group_alias/upgrades/2012100501.php
@@ -0,0 +1,117 @@
+<?php
+/**
+ * GroupAlias -- Create missing aliases
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+global $MIGRATED;
+
+$local_version = (int)elgg_get_plugin_setting('version', 'group_alias');
+
+if (2012022501 <= $local_version) {
+        error_log("Group alias requires no upgrade");
+        return;
+}
+
+elgg_load_library("elgg:group_alias");
+
+function group_alias_filtername($name) {
+        $group_name = str_replace(' ','-' ,$name);
+        $group_name = str_replace(']','' ,$group_name);
+        $group_name = str_replace('[','' ,$group_name);
+        $group_name = strtolower($group_name);
+
+        return $group_name;
+}
+
+function group_alias_get_groupmail($group) {
+        $group_name = group_alias_filtername($group->name);
+        $group_email = $group_name;
+        $parent = get_entity($group->container_guid);
+        if ($parent instanceof ElggGroup) {
+                $group_email = group_alias_filtername($parent->name)."+".$group_email;
+	}
+
+        return $group_email;
+}
+
+
+function group_alias_find_alias($group) {
+	return group_alias_get_groupmail($group);
+}
+
+/**
+ * Save previous pad name, adapt subtype, river, clean up.
+ */
+function group_alias_2012100501($group) {
+	require_once(elgg_get_plugins_path() . 'upgrade-tools/lib/upgrade_tools.php');
+	if (empty($group->alias)) {
+	//if (true) {
+		$alias = group_alias_find_alias($group);
+		$ngroups = elgg_get_entities_from_metadata(array(
+	                'type' => 'group',
+	                'metadata_name' => 'alias',
+	                'metadata_value' => $alias,
+        	        'limit' => 0,
+        	        'count' => true,
+		        ));
+		try {
+			$validates = group_alias_validate($alias);
+		} catch (RegistrationException $e) {
+			$validates = false;
+		}
+		if (!$validates || $ngroups > 1 || ($ngroups == 1 && $alias != $group->alias)) {
+			$alias = elgg_get_friendly_title($group->name);
+			$alias = preg_replace("/-/", "_", $alias);
+			$alias = urldecode($alias);
+			$g = get_group_from_group_alias($alias);
+			if (elgg_instanceof($g, 'group') && $g->getGUID() != $group->guid){
+				$alias .= $group->guid;
+			}
+
+		}
+		if ($group->alias != $alias) {
+			$group->alias = $alias;
+		}
+	}
+	return true;
+}
+
+/*
+ * Run upgrade. First users, then pads
+ */
+// users
+$options = array('type' => 'group', 'limit' => 0);
+
+$MIGRATED = 0;
+
+$previous_access = elgg_set_ignore_access(true);
+$batch = new ElggBatch('elgg_get_entities', $options, "group_alias_2012100501", 100);
+elgg_set_ignore_access($previous_access);
+
+if ($batch->callbackResult) {
+	error_log("Group alias upgrade (201210050) succeeded");
+	elgg_set_plugin_setting('version', 2012022501, 'group_alias');
+} else {
+	error_log("Group alias upgrade (201210050) failed");
+}
diff --git a/mod/group_alias/views/default/group_alias/js.php b/mod/group_alias/views/default/group_alias/js.php
new file mode 100644
index 000000000..b2c2811f5
--- /dev/null
+++ b/mod/group_alias/views/default/group_alias/js.php
@@ -0,0 +1,36 @@
+<?php
+/**
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+?>
+$(function(){
+	$('input.elgg-input-text[name="name"]').keyup(function(){
+		$('input.elgg-input-text[name="alias"][disabled!="disabled"]').val(function(title){
+			return title.replace(/[^\w ]/g, "")
+							.replace(/^\s+/g,'').replace(/\s+$/g,'') //trim
+							.replace(/ /g, "_")
+							.replace(/__/g, "_")
+							.toLowerCase();
+		}($(this).val()));
+	});
+});
diff --git a/mod/group_alias/views/default/input/group_alias.php b/mod/group_alias/views/default/input/group_alias.php
new file mode 100644
index 000000000..467e45c59
--- /dev/null
+++ b/mod/group_alias/views/default/input/group_alias.php
@@ -0,0 +1,31 @@
+<?php
+/**
+ * GroupAlias -- Input a group alias field
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+if ('no' == elgg_get_plugin_setting('changeable_group_alias', 'group_alias')
+	&& elgg_instanceof(elgg_get_page_owner_entity(), 'group')) {
+	$vars['disabled'] = true;
+}
+echo elgg_view('input/text', $vars);
diff --git a/mod/group_alias/views/default/output/group_alias.php b/mod/group_alias/views/default/output/group_alias.php
new file mode 100644
index 000000000..cb8b19756
--- /dev/null
+++ b/mod/group_alias/views/default/output/group_alias.php
@@ -0,0 +1,46 @@
+<?php
+/**
+ * GroupAlias output
+ *
+ * - Only show in the Group Profile
+ * - If linkup is available, hint about the syntax
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+if ('group_profile' != elgg_get_context()) {
+
+    return false;
+
+}
+
+$alias = htmlspecialchars($vars['value'], ENT_QUOTES, 'UTF-8', false);
+$target_url = elgg_get_config('url') . "g/$alias";
+
+if (elgg_is_active_plugin('linkup')) {
+
+    $hint = elgg_echo('linkup:hint:group', array($alias, $target_url));
+
+} else {
+
+    $hint = $target_url;
+
+}
+
+echo "<span title=\"$hint\">$alias </span><span title=\"$hint\" class=\"elgg-icon elgg-icon-info\"></span>";
diff --git a/mod/group_alias/views/default/plugins/group_alias/settings.php b/mod/group_alias/views/default/plugins/group_alias/settings.php
new file mode 100644
index 000000000..d558b4825
--- /dev/null
+++ b/mod/group_alias/views/default/plugins/group_alias/settings.php
@@ -0,0 +1,46 @@
+<?php
+/**
+ * Group Alias plugin settings
+ *
+ * @package        Lorea
+ * @subpackage     GroupAlias
+ *
+ * Copyright 2011-2013 Lorea Faeries <federation@lorea.org>
+ *
+ * This file is part of the GroupAlias plugin for Elgg.
+ *
+ * GroupAlias is free software: you can redistribute it and/or
+ * modify it under the terms of the GNU Affero General Public License
+ * as published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * GroupAlias is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this program. If not, see
+ * <http://www.gnu.org/licenses/>.
+ */
+
+// set default value
+if (!isset($vars['entity']->changeable_group_alias)) {
+	$vars['entity']->changeable_group_alias = 'no';
+}
+
+echo '<div>';
+echo elgg_echo('groups:alias:changeable');
+echo ' ';
+echo elgg_view('input/select', array(
+	'name' => 'params[changeable_group_alias]',
+	'options_values' => array(
+		'no' => elgg_echo('option:no'),
+		'yes' => elgg_echo('option:yes')
+	),
+	'value' => $vars['entity']->changeable_group_alias,
+));
+echo '<p class="tip">';
+echo elgg_echo('groups:alias:changeable:may_break_urls');
+echo '</p>';
+echo '</div>';