cur_el = null;
	hideTimer = null;
	
	function f_show (el) {
		if (el == null || el == cur_el) {
			if ($(el)) $(el).style.visibility = 'hidden';
			cur_el = null;
		} else {
			$(el).style.visibility = 'visible';
			if (cur_el != null) {
				$(cur_el).style.visibility = 'hidden';
			}
			cur_el = el;		
		}
	}
	
	function startHide() {
		if (cur_el != null) {
			hideTimer = setTimeout('f_show(cur_el)',500); //return true;
		}
	}
	
	function stopHide() {
		if (hideTimer != null) {
			clearTimeout(hideTimer);//return true;
		}
	}