Index: branches/version-2_11-dev/data/class/pages/admin/order/LC_Page_Admin_Order_Edit.php
===================================================================
--- branches/version-2_11-dev/data/class/pages/admin/order/LC_Page_Admin_Order_Edit.php	(revision 21101)
+++ branches/version-2_11-dev/data/class/pages/admin/order/LC_Page_Admin_Order_Edit.php	(revision 21117)
@@ -787,5 +787,9 @@
                     $arrValues[$changed_no] = $arrProduct[$key];
                 } else {
-                    $arrValues[] = $arrProduct[$key];
+                    $added_no = 0;
+                    if (is_array($arrExistsProductClassIds)) {
+                        $added_no = count($arrExistsProductClassIds);
+                    }
+                    $arrValues[$added_no] = $arrProduct[$key];
                 }
                 $objFormParam->setValue($key, $arrValues);