Pop up fra Dynamic Drive der ikke virker

Hej

Jeg har hentet følgende fra Dynamic Drive til at lave et pop up

<script language="javascript" type="text/javascript">
<!--
/****************************************************
    Author: Eric King
    Url: http://redrival.com/eak/index.shtml
    This script is free to use as long as this info is left in
    Featured on Dynamic Drive script library (http://www.dynamicdrive.com)
****************************************************/
var win=null;
function NewWindow(mypage,myname,w,h,scroll,pos){
if(pos=="random"){LeftPosition=(screen.width)?Math.floor(Math.random()*(screen.width-w)):100;TopPosition=(screen.height)?Math.floor(Math.random()*((screen.height-h)-75)):100;}
if(pos=="center"){LeftPosition=(screen.width)?(screen.width-w)/2:100;TopPosition=(screen.height)?(screen.height-h)/2:100;}
else if((pos!="center" && pos!="random") || pos==null){LeftPosition=0;TopPosition=20}
settings='width='+w+',height='+h+',top='+TopPosition+',left='+LeftPosition+',scrollbars='+scroll+',location=no,directories=no,status=no,menubar=no,toolbar=no,resizable=yes';
win=window.open(mypage,myname,settings);}
// -->
</script>

og sat følgende link ind på min side

<a href="http://www.best-seat.com/nyhed.html" onclick="NewWindow(this.href,'Nyhedsbrev - tilmelding','600','400','no','center');return false" onfocus="this.blur()">YourLinkText</a>

Problemet er at popup'et bare åbner op som et helt almindeligt browservindue.

Det er første gang jeg overhovedet rør ved Java Scripts.

Er der nogle gode forslag?

Mvh

Mads Nørskov