[as2] Complex Collision Detection

I´d like to know if someone knows a way to do a collision detection for
two movieclips with irregular shapes (complex shapes).
I know about the gskinner´s class, and I can´t use it.
I also know about that empty movieclips around the border of each movieclip.
So, there´s another, free to use, way?

Thank you :slight_smile: