currentMenu = "";
hideTimer = null;
delay = 500;

function menuShow(id){
	if (currentMenu){
		document.getElementById(currentMenu).style.visibility = "hidden";
		clearTimeout(hideTimer);
		hideTimer = null;
	}
	currentMenu = "mainMenu" + id;
	document.getElementById(currentMenu).style.visibility = "visible";
}

function menuHide(id){
	if (currentMenu == "mainMenu" + id){
		document.getElementById(currentMenu).style.visibility = "hidden";
		currentMenu = "";
	}
}

function menuOver(id){
	if (currentMenu == "mainMenu" + id){
		clearTimeout(hideTimer);
		hideTimer = null;
	}
}

function menuOut(id){
	hideTimer = setTimeout("menuHide('" + id + "')", delay);
}