DragAndDrop - OnDrop: Change Position

Somebody can tell me what do i have to add at the 'onDrop : function' in the below script to drop the button at the cursor position after the user released the button ?


var windowObserver =
{
onDragStart : function (element, transferData)
{
var Button = document.getElementById('Button');

transferData.data = new TransferData();
transferData.data.addDataForFlavour('Button-ID', Button);
},

getSupportedFlavours : function ()
{
var flavours = new FlavourSet();
flavours.appendFlavour('Button-ID');
return flavours;
},

onDrop : function (){},
};