Possible Workaround:

Telerik.Web.UI.Grid.PositionDragElement = function(element, mouseEvent)
{    
    var clientX = $telerik.isTouchDevice ? $telerik.getTouchEventLocation(mouseEvent).x : mouseEvent.clientX;
    var clientY = $telerik.isTouchDevice ? $telerik.getTouchEventLocation(mouseEvent).y : mouseEvent.clientY;

    element.style.top = clientY + $telerik.getDocumentElementScrollTop() + 10 + "px";

    element.style.left = clientX + $telerik.getDocumentElementScrollLeft() + 10 + "px";

	if ($telerik.isOpera || $telerik.isTouchDevice)
	{
	    element.style.top = parseInt(element.style.top, 10) - document.body.scrollTop + "px";
	}

};