Sorry, but I've never used cpanm either; from what I understand perlbrew does some kind of mix'n'match with installations; and I seem to recall scanning a post in the last couple of weeks or so that mentioned (as I recall) something about there being problems with perlbrew on Apple.

I'm also not aware if perlbrew comes pre-installed with your OS or if you could safely just delete the whole thing and start over without screwing something else up.

The only suggestion I have is that you post a new top-level SoPW describing your complete system and the problem you are encountering and hope that someone here is familiar enough with your setup to help you sort it out.