var lastMenu = null;
var lastMenuTimeout = null;
function showMenu(t)
{
    el = t.getElementsByTagName('UL')[0];
    if(lastMenu == el) { clearTimeout(lastMenuTimeout); return; }
    if(lastMenu) {
        if(lastMenuTimeout) clearTimeout(lastMenuTimeout);
        lastMenu.style.display = 'none';
        lastMenu = null;
    }

    el.style.display = 'block';
    lastMenu = el;
}
function unshowMenu(t)
{
    lastMenuTimeout = setTimeout("lastMenu.style.display = 'none'; lastMenu = null;", 100);
}