Index: trunk/core/units/categories/categories_tag_processor.php
===================================================================
diff -u -N -r4996 -r4997
--- trunk/core/units/categories/categories_tag_processor.php	(.../categories_tag_processor.php)	(revision 4996)
+++ trunk/core/units/categories/categories_tag_processor.php	(.../categories_tag_processor.php)	(revision 4997)
@@ -221,15 +221,18 @@
 			}
 		}
 
-		if(isset($params['block']))
-		{
+		if (isset($params['block'])) {
 			return $this->PrintList($params);
 		}
-		else
-		{
+		else {
 			$params['block'] = $params['block_main'];
-			$params['row_start_block'] = $params['block_row_start'];
-			$params['row_end_block'] = $params['block_row_end'];
+			if (isset($params['block_row_start'])) {
+				$params['row_start_block'] = $params['block_row_start'];
+			}
+			
+			if (isset($params['block_row_end'])) {
+				$params['row_end_block'] = $params['block_row_end'];
+			}
 			return $this->PrintList2($params);
 		}
 	}