Question on extending MovieClip class

Hi I’ve written a class called FadeControls.as that extends the MovieClip class. In the FLA I’m testing with I have movieclip symbols in the library that I can assign the AS 2.0 Class linkage property to read the FadeControls class and apply to that one symbol.

My question is…is there a way to import that class and have it apply to ALL movieClip instances without having to assign AS 2.0 Class links for every MC in the library? The only way I’ve been able to get the class working is by choosing the AS 2.0 Class for every MC in the library that uses the class…which would be quite a pain for large projects and I’d rather use prototypes in lieu of that. Anyone know how to do this??