var timeout = 500;
var closetimer	= 0;
var ddmenuitem = 0;

function menu_open() {
	menu_canceltimer();
	menu_close();
	ddmenuitem = $(this).find('ul').eq(0).css('visibility', 'visible');
}

function menu_close() {
	if(ddmenuitem) ddmenuitem.css('visibility', 'hidden');
}

function menu_timer() {
	closetimer = window.setTimeout(menu_close, timeout);
}

function menu_canceltimer() {
	if(closetimer) {
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}

$(document).ready(function() {
	$('#mainnavigation > ul > li').bind('mouseover', menu_open);
	$('#mainnavigation > ul > li').bind('mouseout',  menu_timer);
});

document.onclick = menu_close;