var _menuTimer = null;

function showMenu(id) {
	hideMenus();
	var menu = document.getElementById(id);
	if (menu == null) return;
	document.getElementById(id).style.visibility = 'visible';	
}

function hideMenus() {
	var arrMenus = document.getElementsByTagName('ul');
	clearTimeout(_menuTimer);
	for (var i = 0; i < arrMenus.length; i++)
		if (arrMenus[i].className == 'menu')
			arrMenus[i].style.visibility = 'hidden';
}

function startHideTimer(id) {
	_menuTimer = setTimeout('hideMenus()', 400);
}