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;