function getDimensions(element)
{
   for (var lx=0,ly=0;element!=null;lx += element.offsetLeft,ly+=element.offsetTop,element=element.offsetParent);

   return {x:lx,y:ly}
}

function positionMenu(x,y)
{
   if (!x)
   {
      x = 0;
   }

   if (!y)
   {
      y = 0;
   }

   NavMenu.fromTop = getDimensions(document.getElementById('menu')).y + y;
   NavMenu.fromLeft = getDimensions(document.getElementById('menu')).x + x;
}