var sub_menu;
	sub_menu="nothing";

var timerID;		

var wait_menu=2500;

var NS;
var IE;
var NS6;

function sbw()
{
	NS = (document.layers) ? 1 : 0;
	IE = (document.all) ? 1 : 0;
	NS6 = (document.getElementById && !document.all);
}

function offv(sub_menu)
{
	if (sub_menu!="nothing")
	{
		if (NS) {
			document.layers[sub_menu].visibility = "hide";
		} 
		if (IE) {
			document.all[sub_menu].style.visibility = "hidden";
		}
		if (NS6) {
			document.getElementById(sub_menu).style.visibility = "hidden";
		 }

	}
	return true;
}

function clrt()
{
	clearTimeout(timerID);
}

function chv(layername,switcher)
{
	if(switcher>0)
	{
		clrt();
		offv(sub_menu);
		if (NS) {
			document.layers[layername].visibility = "show";
		} 
		if (IE) {
			document.all[layername].style.visibility = "visible";
		}
		if (NS6) {
			document.getElementById(layername).style.visibility = "visible";
	 }
		
		sub_menu=layername;
	}
	else
	{
		timerID=setTimeout("offv('" + layername + "')",wait_menu);
	}
}