Button "Over" State Not Working Within Visible MovieClip

Question

Hi Folks,
My button states aren't working right, and I'm pulling my hair out:
http://www.miklas.org/test/test.htm
The desired behavior is under the "Design..."  button--notice how when you mouseover the "Our Philosophy" link it turns blue? Why isn't  this happening for the "What We Can Do For You" and "Our Process" buttons in the other movieclips?
The document is structured as follows:
MovieClip 1: Design: Your Silent Salesperson
---Text
---Images
---Button: Our Philosophy
MovieClip 2: Who Owns Your Brand
---Text
---Images
---Button: What We Can Do For You
MovieClip 3: What's Your Brand's Persona
---Text
---Images:
---Button: Our Process
DETAILED EXPLANATION:
I have three separate movie clips with a bunch of objects. Using AS3,  I  tween their alpha value from 0 to 1 to make them visible depending on a  user mouseover. As part of each movieclip I have a button. It is text  with an underline; made to look like a hyperlink. When the user mouses  over the text, I want it to change color from orange to blue. This works  on the first movieclip, but doesn't on the second and third! What's  weird is that if I cut-and-paste the button from the second or third  movieclip to the first, the over state works fine. If I set Control  -> Enable Simple Buttons, the over state works fine. But when I  export it to .swf, it doesn't work!?
tyvm!

Answer 1

OK I finally got it! My layers were indeed out of whack--the entire problem was solved by the"setChildIndex" function.
Basically, when the user mouses over the buttons, I fade in the new clip, and set the depth above the other movie clips. Here's the code:
buttons_movieClip.whyDesign_button.addEventListener(
  MouseEvent.MOUSE_OVER,
  function(evt:MouseEvent):void
      if (active != whyDesign_movieClip)
        fade(whyDesign_movieClip);
        setChildIndex(whyDesign_movieClip,3);
        setChildIndex(whoOwns_movieClip,2);
        setChildIndex(persona_movieClip,1);
There is a black background at depth 0. The following forum post helped a lot:
http://www.smithmediafusion.com/blog/?p=435
tyvm!