window.addEvent('domready', function(){

  $('drop_down_menu').getElements('li.menuItem').each(
    function( elem ){
      //alert(elem);
      var list = elem.getElement('div.submenuSlide');
        
      if(list != null){
         
        var myFx = new Fx.Slide(list).hide();
        
        elem.addEvents({
          'mouseenter' : function(){
            myFx.cancel();
            myFx.slideIn();
          },
          'mouseleave' : function(){
            myFx.cancel();
            myFx.slideOut();
          }
        });
        
      }
    }
  );
    
});