function popup_launch ( event )
{
  event = new Event( event );
  event.preventDefault();
  window.open(event.target.href, 'popupWindow','toolbar=no,location=no,directories=no,status=no,menubar=no,resizable=yes,copyhistory=no,scrollbars=yes,width=800,height=500');
}

function popup_bind()
{
  $ES("a.popup").each( function ( a ) {
    a.addEvent( 'click', popup_launch );
  } );
}

window.addEvent( 'domready', popup_bind );