Index: branches/5.0.x/core/units/general/helpers/recursive_helper.php
===================================================================
diff -u -r12117 -r12196
--- branches/5.0.x/core/units/general/helpers/recursive_helper.php	(.../recursive_helper.php)	(revision 12117)
+++ branches/5.0.x/core/units/general/helpers/recursive_helper.php	(.../recursive_helper.php)	(revision 12196)
@@ -1,6 +1,6 @@
 <?php
 /**
-* @version	$Id: recursive_helper.php 11892 2009-07-01 08:35:06Z alex $
+* @version	$Id: recursive_helper.php 12196 2009-08-05 10:25:32Z alex $
 * @package	In-Portal
 * @copyright	Copyright (C) 1997 - 2009 Intechnic. All rights reserved.
 * @license      GNU/GPL
@@ -102,7 +102,7 @@
 				$this->Conn->Query($sql);
 			}
 		}
-		
+
 		/**
 		 * Complete cloning or category with subcategories and subitems
 		 *
@@ -111,14 +111,22 @@
 		function PasteCategory($category_id, $prefix = 'c')
 		{
 			$backup_category_id = $this->Application->GetVar('m_cat_id');
-			
+
+			$src_parent_path = $this->_getParentPath($category_id);
+			$dst_parent_path = $this->_getParentPath($backup_category_id);
+
+			if (substr($dst_parent_path, 0, strlen($src_parent_path)) == $src_parent_path) {
+				// target path contains source path -> recursion
+				return ;
+			}
+
 			// 1. clone category
 			$temp_handler =& $this->Application->recallObject($prefix.'_TempHandler', 'kTempTablesHandler');
 			/* @var $temp_handler kTempTablesHandler*/
 			$temp_handler->BuildTables($prefix, Array($category_id));
 			$new_category_id = array_pop( $temp_handler->CloneItems($prefix, '', Array($category_id)) );
 			$this->Application->SetVar('m_cat_id', $new_category_id);
-			
+
 			$id_field = $this->Application->getUnitOption($prefix, 'IDField');
 			$table_name = $this->Application->getUnitOption($prefix, 'TableName');
 
@@ -190,6 +198,26 @@
 			}
 			return $item_ids;
 		}
+
+		/**
+		 * Returns parent path for given category
+		 *
+		 * @param int $category_id
+		 * @return Array
+		 */
+		function _getParentPath($category_id)
+		{
+			static $cache = Array ();
+
+			if (!array_key_exists($category_id, $cache)) {
+				$sql = 'SELECT ParentPath
+						FROM ' . TABLE_PREFIX . 'Category
+						WHERE CategoryId = ' . $category_id;
+				$cache[$category_id] = $this->Conn->GetOne($sql);
+			}
+
+			return $cache[$category_id];
+		}
 	}
 
 ?>
\ No newline at end of file