(function($){

	$(function(){
		
		$('li.menu_sub').hover(function(){ 
			$("img", this).attr('src', $("img", this).attr('src').replace('_off', '_on'));
			$(this).children("ul").slideDown({duration: 200, easing: "swing", complete: "callback"});
		}, function(){
			$(this).children("ul").slideUp({duration: 200, easing: "swing", complete: "callback"});
			$("img", this).attr('src', $("img", this).attr('src').replace('_on', '_off'));
		});

	});
})(jQuery);