Index: branches/5.0.x/core/kernel/db/cat_event_handler.php
===================================================================
diff -u -N -r12734 -r12789
--- branches/5.0.x/core/kernel/db/cat_event_handler.php	(.../cat_event_handler.php)	(revision 12734)
+++ branches/5.0.x/core/kernel/db/cat_event_handler.php	(.../cat_event_handler.php)	(revision 12789)
@@ -1,6 +1,6 @@
 <?php
 /**
-* @version	$Id: cat_event_handler.php 12734 2009-10-20 19:28:11Z alex $
+* @version	$Id: cat_event_handler.php 12789 2009-10-25 20:56:43Z alex $
 * @package	In-Portal
 * @copyright	Copyright (C) 1997 - 2009 Intechnic. All rights reserved.
 * @license      GNU/GPL
@@ -2246,6 +2246,11 @@
 	 */
 	function processAdditionalCategories(&$object, $mode)
 	{
+		if (!array_key_exists('MoreCategories', $object->VirtualFields)) {
+			// given category item doesn't require such type of processing
+			return ;
+		}
+
 		$process_categories = $object->GetDBField('MoreCategories');
 		if ($process_categories === '') {
 			// field was not in submit & have default value (when no categories submitted, then value is null)