A Simple thing: how to write a simple event listener?

Hello,

First, please understand that I am a n00b and therefore might get terminology etc. wrong.

I am developing for Scaleform (therefore authoring in ActionScript 2.0 for Flash Player 8).

I have a movie clip on stage which is a stack of buttons.

I want to create a simple test, I want a function to fire when the mouse is rolled OFF the BtnList movie clip.

How do I do it?

Here is my current, not-working code:

_root.BtnList.addEventListener(MouseEvent.MOUSE_OUT, EnableToggleCycle);

function EnableToggleCycle(event:MouseEvent):void
{
trace("EnableToggleCycle triggered");
}

Au secours!

Gracias,

-Rick.