submenuitems = 6;
var timerID;

// retrieve current snav element
function getItem (num) {
	e = document.getElementById('snav_'+ num);
	if (e != null) return e;
	else return null;
}

// retrieve current snav element className
function getItemClass (num) {
	e = getItem (num);
	if (e != null) return e.className;
	else return null;
}

// toggle snav element visibility
function toggleSubNav (num, tn_id) {
	var ic = getItemClass (num);
	if (ic == 'subhide' || ic == null) {
		closeSubMenus ();
		getItem (num).className = 'subshow';
		if (timerID) clearTimeout (timerID); // this check doesn't work
		timerID = setTimeout ('closeSubMenus ()', 8000);
	}
	else {
		e = document.getElementById('snav_'+ num);
		if (e != null || e.className == 'subshow') e.className = 'subhide';
		clearTimeout (timerID);
	}
}

// close all others
function closeSubMenus () {
	for (i = 0; i < submenuitems; i++) {
		if (e = getItem (i)) e.className = 'subhide';
	}
}