Menu problem

I am building a menu and for each button of the menu, subbuttons apear beneath it along the menu. And I am having some problems. Each of the menu buttons has animations for rollOver and rollOut. What can I do so that when I move over the subbuttons the menu button won’t start the rollOut animation. I have to extend the hit state. If I put the subbuttons in the same movie clip as the menu button, the animation would be bad because I am doing width, height, x and y tweenings with ActionScript and addind something the the clip would change these properties. Pls help.

Is it possible to extend the hit state of the menu button in some way ?