jQuery: Horizontal Drop Down Menu

gistfile1

// HORIZONTAL DROP DOWN MENU 
	var timeout = 3000;
	var closetimer = 0;
	var navitem = 0;
	
	function nav_open(){
		nav_canceltimer();
	   	nav_close();
	   	navitem = $(this).find('ul').css('visibility', 'visible');
	}
	function nav_close(){ 
		if(navitem) navitem.css('visibility', 'hidden');
	}
	function nav_timer(){
		closetimer = window.setTimeout(nav_close, timeout);
	}
	function nav_canceltimer(){  
		if(closetimer){  
			window.clearTimeout(closetimer);
	        closetimer = null;
	    }
	}
	$('#nav > li').bind('mouseover', nav_open);
    $('#nav > li').bind('mouseout',  nav_timer);
	document.onclick = nav_close;