         var allVisibleColumns:Array = dataGrid.getAllVisibleColumns();
         var pt:Point = new Point(event.stageX, event.stageY);
         pt = dataGrid.globalToLocal(pt);
-
+        lastPt = pt;
         n = allVisibleColumns.length;
         var xx:Number = dataGrid.viewMetrics.left;
         var ww:Number;


        var vsw:int = dataGrid.vScrollBar ? dataGrid.vScrollBar.width : 0;

        var pt:Point = new Point(event.stageX, event.stageY);
        pt = dataGrid.globalToLocal(pt);

        // resize the column
        var widthChange:Number = Math.min(Math.max(minX, pt.x),
            (dataGrid.width / dataGrid.scaleX) - separators[0].width - vsw) - startX;

            if (dataGrid.draggableColumns && visibleColumns[i].draggable)
            {
                startX = NaN;
                
                var sbRoot:DisplayObject = systemManager.getSandboxRoot();
                sbRoot.addEventListener(MouseEvent.MOUSE_MOVE, columnDraggingMouseMoveHandler, true);
                sbRoot.addEventListener(MouseEvent.MOUSE_UP, columnDraggingMouseUpHandler, true);
                sbRoot.addEventListener(SandboxMouseEvent.MOUSE_UP_SOMEWHERE, columnDraggingMouseUpHandler);
                systemManager.deployMouseShields(true);
                dataGrid.movingColumn = visibleColumns[i];
            }
        }
