var currentMenu = null;

if (!document.getElementById)
    document.getElementById = function() { return null; }

function initializeMenu(menuId, actuatorId) {
    var menu = document.getElementById(menuId);
    var actuator = document.getElementById(actuatorId);

    if (menu == null || actuator == null) return;

    actuator.onmouseover = function()
    {
	if (currentMenu == null)
	{   this.showMenu(); }
        else if (currentMenu)
	{   currentMenu.style.visibility = "hidden";
            this.showMenu();
        }
    }
  
    menu.onmouseover = function()
    {
	if (currentMenu)
	{ currentMenu.style.visibility = "visible"; }
    }
  
    actuator.onmouseout = function()
    {
	if (currentMenu)
	{ currentMenu.style.visibility = "hidden"; }
    }
    
    menu.onmouseout = function()
    {
	if (currentMenu)
	{ currentMenu.style.visibility = "hidden"; }
    }

    actuator.showMenu = function()
    {
        menu.style.left = this.offsetLeft + "px";
        menu.style.top = this.offsetTop + this.offsetHeight + "px";
        menu.style.visibility = "visible";
        currentMenu = menu;
    }
}