Well, it's Always been vague how vamps work in Blood Compact, but I'm pretty sure we established the Christian Symbolism thing quite firmly. Then again, that could just be 'Draculan' vampires, and that older strains of vampires may have different weaknesses.

I would not state, however, that vampires from other religions get a get-out-of-jail-free card when it comes to weaknesses, as it's the one thing balancing vamps and humies.