function SwitchMenu(obj)
{
	if(document.getElementById)
	{
		var el = document.getElementById(obj);
		var ar = document.getElementById("menudiv").getElementsByTagName("span");
		if(el.style.display != "block")
		{
			for (var i=0; i<ar.length; i++)
			{
				if (ar[i].className=="submenu")
					ar[i].style.display = "none";
			}
			el.style.display = "block";
		}
		else
		{
			el.style.display = "none";
		}
	}
}