function popup() {
  window.open(this.href, 'snwin', 'scrollbars=yes,width=500,height=380');
  return false;
}
function cklinks() {
for (i=document.links.length; i-->0;)
if (document.links[i].className=='popup')
  document.links[i].onclick=popup;
}
window.onload = cklinks;