Fixed a minor issue in ReplyTo plugin

Author: atelomycterus

ReplyTo/class.replyto.plugin.php

@@ -203,7 +203,7 @@ public function base_commentOptions_handler($sender, $args) {
 
         //Check permission
         if (isset($discussion->PermissionCategoryID)) {
-            $CategoryID = $discussion->CategoryPermissionID;
+            $CategoryID = val('CategoryPermissionID', $discussion);
         } else {
             $CategoryID = $discussion->CategoryID;
         }