Index: maintenance/language/messages.inc
===================================================================
--- maintenance/language/messages.inc	(revision 18862)
+++ maintenance/language/messages.inc	(working copy)
@@ -1250,7 +1250,7 @@
 		'move-watch',
 		'movepagebtn',
 		'pagemovedsub',
-		'pagemovedtext',
+		'pagemoved',
 		'articleexists',
 		'talkexists',
 		'movedto',
Index: includes/Article.php
===================================================================
--- includes/Article.php	(revision 18861)
+++ includes/Article.php	(working copy)
@@ -2216,6 +2216,18 @@
 		$u = new LinksUpdate( $this->mTitle, $poutput );
 		$u->doUpdate();
 
+		# Update categorylinks to a category when it becomes a redirect
+		if ( $this->mTitle->getNamespace() == NS_CATEGORY ) {
+			$rt = Title::newFromRedirect( $text );
+			if( is_object( $rt ) && $rt->getNamespace() == NS_CATEGORY ) {
+				$dbw =& wfGetDB( DB_MASTER );
+				$categorylinks = $dbw->tableName( 'categorylinks' );
+				$sql = "UPDATE $categorylinks SET cl_to=" . $dbw->addQuotes( $rt->getDBkey() ) .
+					" WHERE cl_to=" . $dbw->addQuotes( $this->mTitle->getDbKey() );
+				$dbw->query( $sql, __METHOD__ );
+			}
+		}
+
 		if ( wfRunHooks( 'ArticleEditUpdatesDeleteFromRecentchanges', array( &$this ) ) ) {
 			wfSeedRandom();
 			if ( 0 == mt_rand( 0, 999 ) ) {
Index: includes/Parser.php
===================================================================
--- includes/Parser.php	(revision 18861)
+++ includes/Parser.php	(working copy)
@@ -1757,6 +1757,17 @@
 					wfProfileIn( "$fname-category" );
 					$s = rtrim($s . "\n"); # bug 87
 
+					# Redirect categories - bug 3311
+					$dbr =& wfGetDB( DB_SLAVE );
+					$obj = $dbr->selectRow( array( 'redirect' ),
+						array( 'rd_namespace', 'rd_title' ),
+						array( 'rd_from' => $nt->getArticleID() ),
+						__METHOD__ );
+					if ( $obj && $obj->rd_namespace == NS_CATEGORY ) {
+						# The category redirects to another category; follow it
+						$nt = Title::makeTitle( NS_CATEGORY, $obj->rd_title );
+					}
+
 					if ( $wasblank ) {
 						$sortkey = $this->getDefaultSort();
 					} else {
Index: includes/SpecialMovepage.php
===================================================================
--- includes/SpecialMovepage.php	(revision 18861)
+++ includes/SpecialMovepage.php	(working copy)
@@ -283,7 +283,7 @@
 		$newText = wfEscapeWikiText( $wgRequest->getVal('newtitle') );
 		$talkmoved = $wgRequest->getVal('talkmoved');
 
-		$text = wfMsg( 'pagemovedtext', $oldText, $newText );
+		$text = wfMsg( 'pagemoved', $oldText, $newText );
 		
 		$allowHTML = $wgRawHtml;
 		$wgRawHtml = false;
Index: includes/Title.php
===================================================================
--- includes/Title.php	(revision 18861)
+++ includes/Title.php	(working copy)
@@ -1931,6 +1931,13 @@
 			" AND cl_sortkey=" . $dbw->addQuotes( $this->getPrefixedText() );
 		$dbw->query( $sql, 'SpecialMovepage::doSubmit' );
 
+		# Fixing links to the old category when moving categories
+		if ( $this->getNamespace() == NS_CATEGORY && $nt->getNamespace() == NS_CATEGORY ) {
+			$sql = "UPDATE $categorylinks SET cl_to=" . $dbw->addQuotes( $nt->getDBkey() ) .
+				" WHERE cl_to=" . $dbw->addQuotes( $this->getDbKey() );
+			$dbw->query( $sql, __METHOD__ );
+		}
+
 		# Update watchlists
 
 		$oldnamespace = $this->getNamespace() & ~1;
@@ -2020,7 +2027,11 @@
 
 		# Recreate the redirect, this time in the other direction.
 		$mwRedir = MagicWord::get( 'redirect' );
-		$redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
+		if ( $nt->getNamespace() == NS_IMAGE || $nt->getNamespace() == NS_CATEGORY ) {
+			$redirectText = $mwRedir->getSynonym( 0 ) . ' [[:' . $nt->getPrefixedText() . "]]\n";
+		} else {
+			$redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
+		}
 		$redirectArticle = new Article( $this );
 		$newid = $redirectArticle->insertOn( $dbw );
 		$redirectRevision = new Revision( array(
@@ -2092,7 +2103,11 @@
 
 		# Insert redirect
 		$mwRedir = MagicWord::get( 'redirect' );
-		$redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
+		if ( $nt->getNamespace() == NS_IMAGE || $nt->getNamespace() == NS_CATEGORY ) {
+			$redirectText = $mwRedir->getSynonym( 0 ) . ' [[:' . $nt->getPrefixedText() . "]]\n";
+		} else {
+			$redirectText = $mwRedir->getSynonym( 0 ) . ' [[' . $nt->getPrefixedText() . "]]\n";
+		}
 		$redirectArticle = new Article( $this );
 		$newid = $redirectArticle->insertOn( $dbw );
 		$redirectRevision = new Revision( array(
Index: includes/Namespace.php
===================================================================
--- includes/Namespace.php	(revision 18861)
+++ includes/Namespace.php	(working copy)
@@ -50,7 +50,7 @@
 	 * @return bool
 	 */
 	static function isMovable( $index ) {
-		return !( $index < NS_MAIN || $index == NS_IMAGE  || $index == NS_CATEGORY );
+		return !( $index < NS_MAIN || $index == NS_IMAGE  );
 	}
 
 	/**
Index: languages/messages/MessagesEn.php
===================================================================
--- languages/messages/MessagesEn.php	(revision 18861)
+++ languages/messages/MessagesEn.php	(working copy)
@@ -1959,7 +1959,7 @@
 'move-watch' => 'Watch this page',
 'movepagebtn'	=> 'Move page',
 'pagemovedsub'	=> 'Move succeeded',
-'pagemovedtext' => "Page \"[[$1]]\" moved to \"[[$2]]\".",
+'pagemoved'     => "Page \"[[:$1]]\" moved to \"[[:$2]]\".",
 'articleexists' => 'A page of that name already exists, or the
 name you have chosen is not valid.
 Please choose another name.',
Index: languages/messages/MessagesHe.php
===================================================================
--- languages/messages/MessagesHe.php	(revision 18862)
+++ languages/messages/MessagesHe.php	(working copy)
@@ -1527,7 +1527,7 @@
 'move-watch'              => 'מעקב אחרי דף זה',
 'movepagebtn'             => 'העבר דף',
 'pagemovedsub'            => 'ההעברה הושלמה בהצלחה',
-'pagemovedtext'           => 'הדף "[[$1]]" הועבר לשם "[[$2]]".',
+'pagemoved'               => 'הדף "[[:$1]]" הועבר לשם "[[:$2]]".',
 'articleexists'           => 'קיים כבר דף עם אותו שם, או שהשם שבחרתם אינו חוקי.
 אנא בחרו שם אחר.',
 'talkexists'              => 'הדף עצמו הועבר בהצלחה, אבל דף השיחה לא הועבר כיוון שקיים כבר דף שיחה במיקום החדש. אנא מזגו אותם ידנית.',