MovieClip Inheritance in Flash MX

Okay. This should be a rather simple question, but I can’t find an answer. I’m in the process of making a smallish tile-based game. In it I want to create a tile class (using the prototype function). In this tile class I want to be able to create a MovieClip variable inside of it to hold the actual graphical tile. Whenever you create a movieclip in the library does it create an actual new class inheriting the MovieClip class? or does it just create a certain MovieClip with the right properties?

If I have a movieclip in the library called example and I’m creating this tile class with the prototype.
Can I use:
tile.prototype.mc = new example();

Or is there some other way I need to do this.
I’m using Flash MX.

EDIT: Okay. So, I’ve been searching more and I’ve found the Object.registerClass(MovieClip, Class); Is this a good way to do this? and is it the only way?

[RIGHT]Thanks, SoupHead :yoshi:
[/RIGHT]