Index: branches/version-2_5-dev/data/class/SC_Product.php
===================================================================
--- branches/version-2_5-dev/data/class/SC_Product.php	(revision 18819)
+++ branches/version-2_5-dev/data/class/SC_Product.php	(revision 18820)
@@ -345,4 +345,8 @@
         $results = $this->getProductsClassLevelByProductId($productId);
         $productsClass = array();
+        if (SC_Utils_Ex::isBlank($results["level1"]) && SC_Utils_Ex::isBlank($results["level2"])) {
+            return $results["level"];
+        }
+
         foreach ($results["level1"] as $level1) {
             foreach ($results["level2"] as $level2) {