[flexcoders] Anyway to introspect a Module for a list of Classes?

[Todd]

Hello All,
  I'm trying to figure out the Flex reflection APIs and their
limitations.  I'm looking for a way to get all the Classes in a
Module, or even the main SWF of a given type.  Is there a way to do this?

I've looked at the flash.util:
    getDefenition, 
    describeType,
    getQualifiedClassNae,
    getQualifiedSuperclassName
    etc.
But I dont' see anything useful.

For example, I want to take a SWF and get all classes that extend
MyBaseClass...

Thanks,
Todd