var menu_timeout    = 0;
var menu_closetimer = 0;
var menu_ddmenuitem = 0;

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

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

function menu_timer() {
    menu_closetimer = window.setTimeout(menu_close, menu_timeout);
}

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

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

document.onclick = menu_close;