var isopenSubMenu = null;
var to_close;
var timer;
function closeSubMenu(menu_id) {
	document.getElementById(menu_id).style.visibility = "hidden";
	isopenSubMenu = null;
}

function openSubMenu(menu_id) {
	if (isopenSubMenu) {
		closeSubMenu(isopenSubMenu);
	}
	window.clearTimeout(timer);
	document.getElementById(menu_id).style.visibility = "visible";
	isopenSubMenu = menu_id;
}

function startTimeout(menu_id) {
	to_close = menu_id;
	timer = window.setTimeout("closeSubMenu(to_close)", 1000);
}

function stopTimeout() {
	window.clearTimeout(timer);
}