var timeout         = 500;
var closetimer		= 0;
var ddmenuitem      = 0;
function mopen(id){	
	mcancelclosetime();
	if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';
	ddmenuitem = document.getElementById(id);
	ddmenuitem.style.visibility = 'visible';
}
function mclose() {
	if(ddmenuitem) ddmenuitem.style.visibility = 'hidden';
}
function mclosetime() {
	closetimer = window.setTimeout(mclose, timeout);
}
function mcancelclosetime() {
	if(closetimer) {
		window.clearTimeout(closetimer);
		closetimer = null;
	}
}
document.onclick = mclose;