window.addEvent('domready',function(){
  $$('a').each(function(el){      
    if ( el.getProperty('rel') == 'popup' )
      {
      el.addEvent('click',function(e){
        new Event(e).stop();
        var href =  $(this).getProperty('href');
        href += ( href.contains('?') ) ? '&popup' : '?popup' ;
        produkt_popup( href );    
        });
      }
    });
  });