Index: branches/version-2_11-dev/data/class/pages/products/LC_Page_Products_List.php
===================================================================
--- branches/version-2_11-dev/data/class/pages/products/LC_Page_Products_List.php	(revision 21327)
+++ branches/version-2_11-dev/data/class/pages/products/LC_Page_Products_List.php	(revision 21386)
@@ -425,5 +425,5 @@
 
         if (strlen($searchCondition["where_category"]) >= 1) {
-            $searchCondition['where'] .= " AND T2.".$searchCondition["where_category"];
+            $searchCondition['where'] .= " AND dtb_product_categories.".$searchCondition["where_category"];
             $searchCondition['arrval'] = array_merge($searchCondition['arrval'], $searchCondition['arrvalCategory']);
         }
Index: branches/version-2_11-dev/data/class/SC_Product.php
===================================================================
--- branches/version-2_11-dev/data/class/SC_Product.php	(revision 21352)
+++ branches/version-2_11-dev/data/class/SC_Product.php	(revision 21386)
@@ -74,11 +74,9 @@
     function findProductIdsOrder(&$objQuery, $arrVal = array()) {
         $table = <<< __EOS__
-                 dtb_products AS alldtl
-            JOIN dtb_products_class AS T1
-              ON alldtl.product_id = T1.product_id
-            JOIN dtb_product_categories AS T2
-              ON alldtl.product_id = T2.product_id
-            JOIN dtb_category
-              ON T2.category_id = dtb_category.category_id
+            dtb_products AS alldtl
+            LEFT JOIN dtb_products_class
+                ON alldtl.product_id = dtb_products_class.product_id
+            LEFT JOIN dtb_product_categories
+                ON alldtl.product_id = dtb_product_categories.product_id
 __EOS__;
         $objQuery->setGroupBy('alldtl.product_id');
@@ -119,9 +117,9 @@
     function findProductCount(&$objQuery, $arrVal = array()) {
         $table = <<< __EOS__
-                 dtb_products AS alldtl
-            JOIN dtb_product_categories AS T2
-              ON alldtl.product_id = T2.product_id
-            JOIN dtb_category
-              ON T2.category_id = dtb_category.category_id
+            dtb_products AS alldtl
+            LEFT JOIN dtb_products_class
+                ON alldtl.product_id = dtb_products_class.product_id
+            LEFT JOIN dtb_product_categories
+                ON alldtl.product_id = dtb_product_categories.product_id
 __EOS__;
         $objQuery->setGroupBy('alldtl.product_id');