åben popup ved musen - ret script

har kigget lidt her på eksperten, og brgget lidt sammen, men det funger ikke...
(http://hjem.get2net.dk/Jakob.Aggernaes/temp/exp57415.html)

<script language="javascript" type="text/javascript">


var Ymouse = Xmouse = 0;
var ns4 = (document.layers)?true:false;
var ns6 = (document.getElementById && !document.all)?true:false;


function Mouse( evnt ) {
  Ymouse=(ns4||ns6)?evnt.pageY:event.y;
  Xmouse=(ns4||ns6)?evnt.pageX:event.x;
}; //end Mouse( event object )

if (ns4) {
  window.captureEvents(Event.MOUSEMOVE);
  window.onMouseMove=Mouse;        // catch mouse movement (NS)
} else {
  document.onmousemove=Mouse;      // catch mouse movement (IE)

};

var popVindue;
function popWin(imgUrl,Ymouse,Xmouse){
  popVindue=window.open(imgUrl,"", width=200,height=300,left="+Ymouse+",top="+Xmouse+");
}

function closePopWin(){
  if (popVindue) popVindue.close()
}

</script>



<a href="#" onmouseover="popWin('24.jpg');" onmouseout="closePopWin();">Hvis musen er herover vises der et billede</a>