var testing = "hallo christof";
var oldbox ="n";
function hidebox(thebox)
	{
	if (document.all)
		{
		eval(thebox + ".style.visibility='hidden'")
	}
	else if (document.layers)
		{
		eval("document." + thebox + ".visibility='hide'")
	}
	else if (document.getElementById&&!document.all)
		{
		eval("document.getElementById('" + thebox + "').style.visibility='hidden'")
	}
}

function showbox(thebox)
	{
	// alert(testing);
	if (oldbox == "n") {
		// alert("first window");
	} else {
		hidebox(oldbox);
	}
	oldbox = thebox;
	if (document.all)
		{
		eval(thebox + ".style.visibility='visible'");
	}
	else if (document.layers)
		{
		eval("document." + thebox + ".visibility='show'");
	}
	else if (document.getElementById&&!document.all)
		{
		eval("document.getElementById('" + thebox + "').style.visibility='visible'")
	}
}