window.addEvent("domready", function(){
	new Asset.images(['/images/menu/b1_on.png','/images/menu/b2_on.png','/images/menu/b3_on.png','/images/menu/b4_on.png']);

	$('drop_down_menu').getElements('li.menu').each( function( elem ){
		var list = elem.getElement('ul.links'); 
		var myFx = new Fx.Slide(list, {transition: Fx.Transitions.Bounce.easeOut}).hide(); 
		var div = elem.getElement('img');

		elem.addEvents({
			'mouseenter' : function(){ 
				var path = 'images/menu/'+div.id+'_on.png'
				div.setProperty('src', path);
				myFx.cancel();
				myFx.slideIn(); 
			},
			'mouseleave' : function(){ 
				var path = 'images/menu/'+div.id+'_out.png'
				myFx.cancel();
				myFx.slideOut(); 
				div.setProperty('src', path);
			}
		});	
	})
});