Help finding obscure Bane weapon ability that targets classes

[Jowgen]

I recently came across a WSA tucked away in some web enhancement or adventure module that was basically Bane, but instead of creature type it triggered of character class. I think it was just a +1, maybe a a +2, but I am positive I saw it. Sadly I didn't make a note of where it was (as it's not that useful), but now I need the reference.

Does anyone happen to know where I saw this?

[daremetoidareyo]

Babe of infidels from power of faerun?
Basically favored enemy (church).

[Braininthejar2]

Complete arcane added a magebane weapon, which was a bane of all arcane casters.