Button Prototype : Is this possible?

Hi i need some help

I would like all my buttons to set a variable in _level0 whenever the button Events are triggered.

The challenge is, that you should still be able to use myMc.onRollOver = function(){trace(“myOtherStuff”)}, as normal…later on…

atleast that seems to be the challenge, as its pretty easy to make a prototype button, and define onRelease etc etc…but thats no good…