I basically agree with Tye's reponse. However, since you asked so specifically:

Anyone know if some CPAN modules can help get this right?

This makes me think of memoize. Would it be possible to memoize require? Aside from the bootstrap mess of requiring Memoize in order to memoize require before you require other things, I'd suspect that there are many other problems lurking, which is why I agree that it should probably be fixed in Perl instead.

update: and now that I think about it, it would prevent (or have to be turned off for) things like ikegami's:

   # Fix something
   ...

   # Try again
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