Index: trunk/core/units/general/cat_event_handler.php
===================================================================
diff -u -N -r8546 -r8562
--- trunk/core/units/general/cat_event_handler.php	(.../cat_event_handler.php)	(revision 8546)
+++ trunk/core/units/general/cat_event_handler.php	(.../cat_event_handler.php)	(revision 8562)
@@ -360,9 +360,15 @@
 
 			if ((string) $parent_cat_id != 'any') {
 				if ($event->getEventParam('recursive')) {
-					$current_path = $this->Conn->GetOne('SELECT ParentPath FROM '.TABLE_PREFIX.'Category WHERE CategoryId='.$parent_cat_id);
-					$subcats = $this->Conn->GetCol('SELECT CategoryId FROM '.TABLE_PREFIX.'Category WHERE ParentPath LIKE "'.$current_path.'%" ');
-					$object->addFilter('category_filter', TABLE_PREFIX.'CategoryItems.CategoryId IN ('.implode(', ', $subcats).')');
+					if ($parent_cat_id > 0) {
+						// not "Home" category
+						$sql = 'SELECT TreeLeft, TreeRight
+								FROM '.TABLE_PREFIX.'Category
+								WHERE CategoryId = '.$parent_cat_id;
+						$tree_indexes = $this->Conn->GetRow($sql);
+
+						$object->addFilter('category_filter', TABLE_PREFIX.'Category.TreeLeft BETWEEN '.$tree_indexes['TreeLeft'].' AND '.$tree_indexes['TreeRight']);
+					}
 					$object->addFilter('primary_filter', 'PrimaryCat = 1');
 				}
 				else {