function doPopups() {
  if (!document.getElementsByTagName) return false;
  var links=document.getElementsByTagName("a");
  for (var i=0; i < links.length; i++) {
    if (links[i].getAttribute('rel') == "popup") {
      links[i].onclick=function() {
            window.open(this.href, "newwin","top=0,left=0,width=729,height=480,scrollbars=yes");
            return false;
            }
    }
  }
}

addLoadEvent(doPopups);