// cleanup temporary data at the end
          stop: function(ev, ui) {
            ids = dragGroups[ui.helper[0].id];          
            for (var i = 0; i < ids.length; i++) {          
               $('#'+ids[i]).removeData("top0");
               $('#'+ids[i]).removeData("left0");
            }        
          }        
        });
      });
    </script>