Index: branches/5.2.x/core/kernel/db/dbitem.php
===================================================================
diff -u -N -r14699 -r14799
--- branches/5.2.x/core/kernel/db/dbitem.php	(.../dbitem.php)	(revision 14699)
+++ branches/5.2.x/core/kernel/db/dbitem.php	(.../dbitem.php)	(revision 14799)
@@ -1,6 +1,6 @@
 <?php
 /**
-* @version	$Id: dbitem.php 14699 2011-10-26 11:39:38Z alex $
+* @version	$Id: dbitem.php 14799 2011-11-27 19:15:42Z alex $
 * @package	In-Portal
 * @copyright	Copyright (C) 1997 - 2009 Intechnic. All rights reserved.
 * @license      GNU/GPL
@@ -353,12 +353,9 @@
 		$ret = '';
 
 		foreach ($keys_hash as $field => $value) {
-			if ( !preg_match('/\./', $field) ) {
-				$ret .= '(`' . $this->TableName . '`.' . $field . ' = ' . $this->Conn->qstr($value) . ') AND ';
-			}
-			else {
-				$ret .= '(' . $field . ' = ' . $this->Conn->qstr($value) . ') AND ';
-			}
+			$value_part = is_null($value) ? ' IS NULL' : ' = ' . $this->Conn->qstr($value);
+
+			$ret .= '(' . (strpos($field, '.') === false ? '`' . $this->TableName . '`.' : '') . $field . $value_part . ') AND ';
 		}
 
 		return substr($ret, 0, -5);