var currentTimer;
var previousMenuItem;

function MenuItem(menuItemName, show)
{
    document.getElementById(menuItemName).className = (show == true)? "SubMenu" : "SubMenuHidden";
}

function CancelTimer()
{
    clearInterval(currentTimer);
}

function Menu(menuItemName, show)
{
    if(previousMenuItem && previousMenuItem != menuItemName)
    {
	    MenuItem(previousMenuItem, false);
	    CancelTimer();
    }
    previousMenuItem = menuItemName;
    if (show)
    {
	    CancelTimer();
	    MenuItem(menuItemName, show);
	    return;
    }
    currentTimer = setTimeout("MenuItem('" + menuItemName + "'," + show + ")", 500);
}