var timeout = 0;
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;