You're innovating faster than I can keep up with it. :-)

I'm glad to see this appear finally, as "foreign inheritance" is one of the other big deals of the inside-out technique. (I like that term -- I've been searching for a good term for it for the seminar that I mentioned in Seeking inside-out object implementations, so I'll have to steal it and credit you.)

Can you talk about the design choices you've made a little bit more? From a quick skim of the code, it looks like you're using some sort of facade pattern (er, adaptor pattern, whatever) in the AUTOLOAD to check method calls against the foreign object(s), rather than using a foreign object as the blessed reference directly with the @ISA array. That does allow multiple foreign objects, but at the cost of incremental indirection.