      */
     private function track_rollOverHandler(event:MouseEvent):void
     {
-        // TODO (klin): Fix up roll over/roll out handling so that
-        // it works with animation.
         if (trackScrolling && trackScrollTimer)
             trackScrollTimer.start();
     }

     */
    protected function button_buttonDownHandler(event:Event):void
    {
        // Make sure we finish any running page animation before starting
        // to step.
        if (!isStepping)
            stopAnimation();
        
        var increment:Boolean = (event.target == incrementButton);
        
        // Dispatch changeStart for the first step if we can make a step.
        if (!isStepping && 
            ((increment && value < maximum) ||
                (!increment && value > minimum)))
        {
            dispatchEvent(new FlexEvent(FlexEvent.CHANGE_START));
            isStepping = true;
            systemManager.getSandboxRoot().addEventListener(MouseEvent.MOUSE_UP, 
                button_buttonUpHandler, true);
            systemManager.getSandboxRoot().addEventListener(
                SandboxMouseEvent.MOUSE_UP_SOMEWHERE, button_buttonUpHandler);
        }
        
        // Noop if we're currently running a stepping animation. We get
        // called repeatedly here due to the button's autoRepeat
        if (!steppingDown && !steppingUp)
        {
            // FIXME (chaase): first step is non-animated, just to simplify the delayed
            // start of the animated stepping. Seems okay, but worth thinking
            // about whether we should animate the first step too
            changeValueByStep(increment);
            
            // Only animate if smoothScrolling enabled and we're not at the end already
            if (getStyle("smoothScrolling") &&
                ((increment && value < maximum) ||

    mx_internal function viewportVerticalScrollPositionChangeHandler(event:PropertyChangeEvent):void
    {
    }   
	
	//---------------------------------
	// Thumb dragging handlers
	//---------------------------------
	
	/**
	 *  @private
	 */
	override protected function thumb_mouseDownHandler(event:MouseEvent) : void
	{
		// Stop animation before thumb dragging
		if (animatingSinglePage)
		{
			animationEndHandler(animator);
			animator.stop();
		}
		
		super.thumb_mouseDownHandler(event);
	}
	
    //---------------------------------
    // Mouse up/down handlers
    //---------------------------------
