Flex 3 - Using custom tooltips

I'm using the tooltipManager as described HERE.

I want to display a custom tooltip for the buttons of a buttonbar.

The buttonbar's declaration is as follow:

<mx:ButtonBar id="topToolbar" height="30" dataProvider="{topToolbarProvider}"
            iconField="icon" itemClick="topToolbarHandler(event)"
            buttonStyleName="topButtonBarButtonStyle"
            toolTipField="tooltip"/>

Until here, everything works fine. I do see the proper text displaying in a tooltip.

Then, I created a custom tooltip manager using the tutorial quoted previously:

public class TooltipsManager
    {
        private var _customToolTip:ToolTip;

        public function TooltipsManager()
        {
        }

        public function showToolTipRight(evt:MouseEvent, text:String):void
        {
            var pt:Point = new Point(evt.currentTarget.x, evt.currentTarget.y);

            // Convert the targets 'local' coordinates to 'global' -- this fixes the
            // tooltips positioning within containers.
            pt = evt.currentTarget.parent.contentToGlobal(pt);

            customToolTip = ToolTipManager.createToolTip(text, pt.x, pt.y, "errorTipRight") as ToolTip;
            customToolTip.setStyle("borderColor", "0xababab");  

            // Move the tooltip to the right of the target
            var xOffset:int = evt.currentTarget.width + 5;//(customToolTip.width - evt.currentTarget.width) / 2;
            customToolTip.x += xOffset;        
        }

        public function showToolTipAbove(evt:MouseEvent, text:String):void
        {
            var pt:Point = new Point(evt.currentTarget.x, evt.currentTarget.y);

            // Convert the targets 'local' coordinates to 'global' -- this fixes the
            // tooltips positioning within containers.
            pt = evt.currentTarget.parent.contentToGlobal(pt);

            customToolTip = ToolTipManager.createToolTip(text, pt.x, pt.y, "errorTipAbove") as ToolTip;
            customToolTip.setStyle("borderColor", "#ababab");

            // Move tooltip below target and add some padding
            var yOffset:int =  customToolTip.height + 5;
            customToolTip.y -= yOffset;    
        }

        public function showToolTipBelow(evt:MouseEvent, text:String):void
        {

            var pt:Point = new Point(evt.currentTarget.x, evt.currentTarget.y);

            // Convert the targets 'local' coordinates to 'global' -- this fixes the
            // tooltips positioning within containers.
            pt = evt.currentTarget.parent.contentToGlobal(pt);

            customToolTip = ToolTipManager.createToolTip(text, pt.x, pt.y, "errorTipBelow") as ToolTip;
            customToolTip.setStyle("borderColor", "ababab");

            // Move tooltip below the target
            var yOffset:int =  evt.currentTarget.height + 5;
            customToolTip.y += yOffset;        
        }

        // Remove the tooltip
        public function killToolTip():void
        {
            ToolTipManager.destroyToolTip(customToolTip);
        }

        [Bindable]
        public function get customTooltip():ToolTip { return _customToolTip; }
        public function set customTooltip(t:ToolTip):void { _customToolTip = t; }

    }

Now, this is where I start having issues...
I'm trying to get to use this custom tooltip, but I don't know how to get the buttonbar to take it into account.

I created a function to see when could I call the functions in my TooltipsManager:

public function showTopToolbarTooltip(e:ToolTipEvent):void{
            trace('blabla');
        }

But it would seem that it's never taken into account. I've put this function in different buttonbar's events: tooltipcreate, tooltipstart, tooltipend but nothing happens. Not a single trace...

Could anyone tell me where to call the function of my tooltipManager?

Thanks a lot for your help.
Kind regards,
BS_C3

Actually, skipped a part of the tutorial =_= Attaching the functions to the mouseover/out events... Sorry for that.