diff --git a/checkin_notes b/checkin_notes
index e56da62ecd..5fdeea3b8b 100755
--- a/checkin_notes
+++ b/checkin_notes
@@ -12506,3 +12506,20 @@ David  9 Nov 2006
 		cpu_sched.C
 		cs_prefs.C
 		cs_scheduler.C
+            
+Rytis  10 Nov 2006
+    - User web: forum thread locking.
+        
+        NOTE: requires DB update.
+
+    html/
+        inc/
+            forum.inc
+            forum_thread.inc
+        user/
+            forum_forum.php
+            forum_reply.php
+            forum_moderate_thread_action.php
+            forum_thread.php
+        ops/
+            db_update.php
\ No newline at end of file
diff --git a/html/inc/forum.inc b/html/inc/forum.inc
index d3b98297ef..de9ad6163c 100644
--- a/html/inc/forum.inc
+++ b/html/inc/forum.inc
@@ -33,7 +33,11 @@ define("EXCERPT_LENGTH", "120");
 
 define('NEW_IMAGE', 'img/unread_post.png');
 define('NEW_IMAGE_STICKY', 'img/unread_sticky.png');
-define('STICKY_IMAGE', 'img/sticky_post.png');
+define('NEW_IMAGE_LOCKED', 'img/unread_locked.png');
+define('NEW_IMAGE_STICKY_LOCKED', 'img/unread_sticky_locked.png');
+define('IMAGE_STICKY', 'img/sticky_post.png');
+define('IMAGE_LOCKED', 'img/locked_post.png');
+define('IMAGE_STICKY_LOCKED', 'img/sticky_locked_post.png');
 define('NEW_IMAGE_HEIGHT','15');
 define('EMPHASIZE_IMAGE', 'img/emphasized_post.png');
 define('EMPHASIZE_IMAGE_HEIGHT','15');
diff --git a/html/inc/forum_thread.inc b/html/inc/forum_thread.inc
index 683cd3cfdf..cb09fb6017 100644
--- a/html/inc/forum_thread.inc
+++ b/html/inc/forum_thread.inc
@@ -124,6 +124,21 @@ class Thread {
         return $result;
     }
     
+    /**
+     * Return thread lock state.
+     **/
+    function isLocked(){
+        return $this->dbObj->locked;
+    }
+    
+    /**
+     * Update thread lock state.
+     **/
+    function setLocked($bool){
+        $result = $this->dbhandler->updateThread($this, "locked", $bool?1:0);
+        return $result;
+    }
+    
     /**
      * Return even more fields from the thread
      **/
diff --git a/html/ops/db_update.php b/html/ops/db_update.php
index 262c18e894..fdb0b78d38 100644
--- a/html/ops/db_update.php
+++ b/html/ops/db_update.php
@@ -342,6 +342,10 @@ function update_10_26_2006() {
     do_query("ALTER TABLE team ADD INDEX team_userid (userid)");
 }
 
-//update_10_26_2006();
+function update_11_10_2006() {
+    do_query("ALTER TABLE `thread` ADD `locked` SMALLINT NOT NULL DEFAULT '0'");
+}
+
+//update_11_10_2006();
 
 ?>
diff --git a/html/user/forum_forum.php b/html/user/forum_forum.php
index 177a2e424f..e2ad901542 100644
--- a/html/user/forum_forum.php
+++ b/html/user/forum_forum.php
@@ -26,7 +26,7 @@ if (!$sort_style) {
 } else {
     // set the sort style
     if ($user){
-	$user->setForumSortStyle($sort_style);
+        $user->setForumSortStyle($sort_style);
     } else {
         list($old_style,$thread_style)=explode("|",$_COOKIE['sorting']);
         setcookie('sorting', implode("|",array($sort_style,$thread_style)), time()+3600*24*365);
@@ -115,15 +115,33 @@ function show_forum($forum, $start, $sort_style, $user) {
         if ($thread->isHidden()) {
             echo "X";
         }
-        if ($unread && !$thread->isSticky()) {
-            echo "<img src=\"".NEW_IMAGE."\" alt=\"Unread post(s)\">";
-        }
-        elseif($unread) {
-            echo "<img src=\"".NEW_IMAGE_STICKY."\" alt=\"Unread post(s)\">";
-        }
-        elseif($thread->isSticky()) {
-            echo "<img src=\"".STICKY_IMAGE."\" alt=\"Sticky\">";
-        }
+	if ($unread) {
+	    if ($thread->isSticky()) {
+		if ($thread->isLocked()) {
+        	    echo "<img src=\"".NEW_IMAGE_STICKY_LOCKED."\" alt=\"Unread post(s), sticky, thread locked\">";
+		} else {
+        	    echo "<img src=\"".NEW_IMAGE_STICKY."\" alt=\"Unread post(s), sticky\">";
+		}
+	    } else {
+		if ($thread->isLocked()) {
+        	    echo "<img src=\"".NEW_IMAGE_LOCKED."\" alt=\"Unread post(s), thread locked\">";
+		} else {
+        	    echo "<img src=\"".NEW_IMAGE."\" alt=\"Unread post(s)\">";
+		}
+	    }
+	} else {
+	    if ($thread->isSticky()) {
+		if ($thread->isLocked()) {
+        	    echo "<img src=\"".IMAGE_STICKY_LOCKED."\" alt=\"Sticky, thread locked\">";
+		} else {
+        	    echo "<img src=\"".IMAGE_STICKY."\" alt=\"Sticky\">";
+		}
+	    } else {
+		if ($thread->isLocked()) {
+        	    echo "<img src=\"".IMAGE_LOCKED."\" alt=\"Thread locked\">";
+		}
+	    }
+	}
         echo "</nobr></td>";
 
         $titlelength = 48;
diff --git a/html/user/forum_moderate_thread_action.php b/html/user/forum_moderate_thread_action.php
index 8d2581e940..93ffe0af4d 100644
--- a/html/user/forum_moderate_thread_action.php
+++ b/html/user/forum_moderate_thread_action.php
@@ -38,6 +38,10 @@ if ($action=="hide"){
     $result = $thread->setSticky(true);
 } elseif ($action=="desticky"){
     $result = $thread->setSticky(false);
+} elseif ($action == "lock") {
+    $result = $thread->setLocked(true);
+} elseif ($action == "unlock") {
+    $result = $thread->setLocked(false);
 } elseif ($action=="move"){
     $forum = new Forum(post_int('forumid'));
     $result = $thread->moveTo($forum);
diff --git a/html/user/forum_reply.php b/html/user/forum_reply.php
index 199aa079ab..cc58385df8 100644
--- a/html/user/forum_reply.php
+++ b/html/user/forum_reply.php
@@ -14,6 +14,12 @@ $logged_in_user = re_get_logged_in_user(true);
 check_banished($logged_in_user);
 
 $thread = new Thread (get_int('thread'));
+
+if ($thread->isLocked() && !$logged_in_user->isSpecialUser(S_MODERATOR)
+    && !$logged_in_user->isSpecialUser(S_ADMIN)) {
+    error_page("This thread is locked. Only forum moderators and administrators are allowed to post there.");
+}
+
 $forum = $thread->getForum();
 $category = $forum->getCategory();
 
diff --git a/html/user/forum_thread.php b/html/user/forum_thread.php
index cfea5afe42..ae6cce4be6 100644
--- a/html/user/forum_thread.php
+++ b/html/user/forum_thread.php
@@ -92,7 +92,10 @@ if (($thread->isHidden()) && $logged_in_user && (!$logged_in_user->isSpecialUser
         <table width=\"100%\" cellspacing=0 cellpadding=0>
         <tr>
         <td align=\"left\">";
-    echo $reply_text = "<a href=\"forum_reply.php?thread=".$thread->getID()."#input\">".tr(FORUM_THREAD_REPLY)."</a><br>";
+        
+    if (!$thread->isLocked() || ($logged_in_user && $logged_in_user->isSpecialUser(S_MODERATOR))) {
+        echo $reply_text = "<a href=\"forum_reply.php?thread=".$thread->getID()."#input\">".tr(FORUM_THREAD_REPLY)."</a><br>";
+    }
 
     if ($is_subscribed) {
         echo tr(FORUM_THREAD_SUBSCRIBED)." ";
@@ -103,16 +106,21 @@ if (($thread->isHidden()) && $logged_in_user && (!$logged_in_user->isSpecialUser
 
     //If the logged in user is moderator enable some extra features
     if ($logged_in_user && $logged_in_user->isSpecialUser(S_MODERATOR)){
-	if ($thread->isHidden()){
-	    echo "<br /><a href=\"forum_moderate_thread_action.php?action=unhide&amp;thread=".$thread->getID()."\">Un-Delete this thread</a>";
-	} else {
-	    echo "<br /><a href=\"forum_moderate_thread.php?action=hide&amp;thread=".$thread->getID()."\">Delete this thread</a>";
-	}
-	if($thread->isSticky()){
-	    echo "<br /><a href=\"forum_moderate_thread_action.php?action=desticky&amp;thread=".$thread->getID()."\">De-sticky this thread</a>"; 
-	} else {
-	    echo "<br /><a href=\"forum_moderate_thread_action.php?action=sticky&amp;thread=".$thread->getID()."\">Make this thread sticky</a>";
-	}	
+	    if ($thread->isHidden()){
+	        echo "<br /><a href=\"forum_moderate_thread_action.php?action=unhide&amp;thread=".$thread->getID()."\">Un-Delete this thread</a>";
+	    } else {
+	        echo "<br /><a href=\"forum_moderate_thread.php?action=hide&amp;thread=".$thread->getID()."\">Delete this thread</a>";
+	    }
+	    if ($thread->isSticky()){
+	        echo "<br /><a href=\"forum_moderate_thread_action.php?action=desticky&amp;thread=".$thread->getID()."\">De-sticky this thread</a>"; 
+	    } else {
+	        echo "<br /><a href=\"forum_moderate_thread_action.php?action=sticky&amp;thread=".$thread->getID()."\">Make this thread sticky</a>";
+	    }
+        if ($thread->isLocked()) {
+            echo "<br /><a href=\"forum_moderate_thread_action.php?action=unlock&amp;thread=".$thread->getID()."\">Unlock thread</a>";
+        } else {
+            echo "<br /><a href=\"forum_moderate_thread_action.php?action=lock&amp;thread=".$thread->getID()."\">Lock thread</a>";
+        }
         echo "<br /><a href=\"forum_moderate_thread.php?action=move&amp;thread=".$thread->getID()."\">Move this thread</a>";
         echo "<br /><a href=\"forum_moderate_thread.php?action=title&amp;thread=".$thread->getID()."\">Edit thread title</a>";
     }
diff --git a/html/user/img/locked_post.png b/html/user/img/locked_post.png
new file mode 100644
index 0000000000..eb13ee1610
Binary files /dev/null and b/html/user/img/locked_post.png differ
diff --git a/html/user/img/sticky_locked_post.png b/html/user/img/sticky_locked_post.png
new file mode 100644
index 0000000000..a754718ab4
Binary files /dev/null and b/html/user/img/sticky_locked_post.png differ
diff --git a/html/user/img/unread_locked.png b/html/user/img/unread_locked.png
new file mode 100644
index 0000000000..e089bae91a
Binary files /dev/null and b/html/user/img/unread_locked.png differ
diff --git a/html/user/img/unread_sticky_locked.png b/html/user/img/unread_sticky_locked.png
new file mode 100644
index 0000000000..5e5ff645b8
Binary files /dev/null and b/html/user/img/unread_sticky_locked.png differ