// "mouseover" event handler for the root menu
    function onMenuBarMouseOver(p_sType, p_aArguments, p_oMenu) {
        if(g_nTimeoutId) {
            window.clearTimeout(g_nTimeoutId);
        }
    }

    // "mouseover" event handler for each submenu
    function onSubmenuMouseOver(p_sType, p_aArguments, p_oMenu) {
        if(g_nTimeoutId) {
            window.clearTimeout(g_nTimeoutId);
        }
    }


    // "mouseout" event handler for each submenu
    function onSubmenuMouseOut(p_sType, p_aArguments, p_oMenu) {
        function hideMenu() {
            p_oMenu.hide();
        }

        if(g_nTimeoutId) {
            window.clearTimeout(g_nTimeoutId);
        }
        g_nTimeoutId = window.setTimeout(hideMenu, 750);
    }


    // "mousedown" handler for the document
    function onDocumentMouseDown(p_oEvent) {
        overlayManager.hideAll();
    }


    // "mouseover" handler for each item in the menu bar
    function onMenuBarItemMouseOver(p_sType, p_aArguments, p_oMenuItem) {
        var oActiveItem = this.parent.activeItem;
    
        // Hide any other submenus that might be visible
        if(oActiveItem && oActiveItem != this) {
            this.parent.clearActiveItem();
        }
    
        // Select and focus the current MenuItem instance
        this.cfg.setProperty("selected", true);
        this.focus();
    
        // Show the submenu for this instance
        var oSubmenu = this.cfg.getProperty("submenu");
        if(oSubmenu) {
            oSubmenu.show();
        }
    };

    // "mouseout" handler for each item in the menu bar
    function onMenuBarItemMouseOut(p_sType, p_aArguments, p_oMenuItem) {
        this.cfg.setProperty("selected", false);
    
        var oSubmenu = this.cfg.getProperty("submenu");
        if(oSubmenu) {
            var oEvent = p_aArguments[0],
                oRelatedTarget = YAHOO.util.Event.getRelatedTarget(oEvent);
            if(
                !(
                    oRelatedTarget == oSubmenu.element || 
                    this._oDom.isAncestor(oSubmenu.element, oRelatedTarget)
                )
            ) {
                oSubmenu.hide();
            }
        }
    };


    // "load" handler for the window
    function onWindowLoad() {
        var oMenuBar = new YAHOO.widget.MenuBar("topRootMenuDiv");
        var i = oMenuBar.getItemGroups()[0].length - 1,
            oMenuItem,
            oSubmenu,               
            aSubmenuItems,
            nSubmenuItems;

        do {
            oMenuItem = oMenuBar.getItem(i);
            aSubmenuItems = g_RootMenu[oMenuItem.element.id];
            if(aSubmenuItems) {
                // Create a submenu
                oSubmenu = new YAHOO.widget.Menu(
                                (oMenuItem.element.id + "menu"), {zIndex: 10000, iframe: true}
                            );
                            
                // Add a "mouseover" event handler to the submenu
                oSubmenu.mouseOverEvent.subscribe(
                        onSubmenuMouseOver, 
                        oSubmenu, 
                        true
                    );

                // Add a "mouseout" event handler to the submenu
                oSubmenu.mouseOutEvent.subscribe(
                        onSubmenuMouseOut,
                        oSubmenu, 
                        true
                    );

                // Add items to the submenu
                nSubmenuItems = aSubmenuItems.length;
                for(var n=0; n<nSubmenuItems; n++) {
                    oSubmenu.addItem(
                        new YAHOO.widget.MenuItem(
                            aSubmenuItems[n].text, 
                            { url: aSubmenuItems[n].url}
                            )
                        );
                }

                // Add the submenu to its parent item in the main menu
                oMenuItem.cfg.setProperty("submenu", oSubmenu);
                overlayManager.register(oSubmenu);
            }
        
        }
        while(i--);
        // Render the menubar and corresponding submenus
        oMenuBar.render();
        /*
            Add a "mouseover" and "mouseout" event handler each item 
            in the menu bar 
        */               

        var aMenuBarItems = oMenuBar.getItemGroups()[0],
            i = aMenuBarItems.length - 1;

        do {

            aMenuBarItems[i].mouseOverEvent.subscribe(
                onMenuBarItemMouseOver, 
                this
            );

            aMenuBarItems[i].mouseOutEvent.subscribe(
                onMenuBarItemMouseOut, 
                this
            );
        
        }
        while(i--);


        // Add a "mouseover" handler to the menubar

        oMenuBar.mouseOverEvent.subscribe(
                onMenuBarMouseOver, 
                oMenuBar, 
                true
            );


        // Add a "mousedown" handler to the document
        YAHOO.util.Event.addListener(
                document, 
                "mousedown", 
                onDocumentMouseDown
            );
    }