Index: trunk/kernel/include/category.php
===================================================================
diff -u -N -r3255 -r3268
--- trunk/kernel/include/category.php	(.../category.php)	(revision 3255)
+++ trunk/kernel/include/category.php	(.../category.php)	(revision 3268)
@@ -59,15 +59,17 @@
 		$db =& GetADODBConnection();
 	
 		$sql = 'SELECT CategoryId FROM '.$this->tablename.' WHERE (Filename = '.$db->qstr($filename).') AND (ParentId = '.$m_var_list['cat'].')';
-		$category_id = $db->GetOne($sql);
+		$found_category_ids = $db->GetCol($sql);
 		$has_page = preg_match('/(.*)_([\d]+)([a-z]*)$/', $filename, $rets);
-		if( ($category_id != $this->UniqueId()) || $has_page ) // other category has same filename as ours OR we have filename, that ends with _number
+		
+		$duplicates_found = (count($found_category_ids) > 1) || ($found_category_ids && $found_category_ids[0] != $this->UniqueId());
+		if ($duplicates_found || $has_page)
 		{
-			$append = $category_id ? 'a' : '';
+			$append = $duplicates_found ? '_a' : '';
 			if($has_page)
 			{
 				$filename = $rets[1].'_'.$rets[2];
-				$append = $rets[3] ? $rets[3] : 'a';
+				$append = $rets[3] ? $rets[3] : '_a';
 			}
 			
 			$sql = 'SELECT CategoryId FROM '.$this->tablename.' WHERE (Filename = %s) AND (CategoryId != '.$this->UniqueId().') AND (ParentId = '.$m_var_list['cat'].')';