var visibleSubmenu = 0;
    var timeout = 0;

    function hasVisibleSubmenu()
    {
        if(visibleSubmenu) {
            return true;
        }
        return false;
    }

    function isTimed()
    {
        if(timeout) {
            return true;
        }
        return false;
    }

    function showSubmenu(id)
    {
        var submenu = document.getElementById(id);

        if(hasVisibleSubmenu()) {
            hideVisibleSubmenu();
        }
        if(isTimed()) {
            window.clearTimeout(timeout);
        }
        makeVisible(submenu);
    }

    function timedHideVisibleSubmenu()
    {
        timeout = window.setTimeout("hideVisibleSubmenu()", 2000);
    }

    function hideVisibleSubmenu()
    {
        makeHidden(visibleSubmenu);
    }

    function makeHidden(element)
    {
        element.style.visibility = "hidden";
    }

    function makeVisible(element)
    {
        element.style.visibility = "visible";
        visibleSubmenu = element;
    }