Ow well in that case I don't think you need a Cross. I found this site because those two were annoying and I was bored- it said "Christian symbols may be replaced with other religious symbols according to the belief system of the wielder and/or vampire. In other words, if a person, confronted by a hungry and hostile vampire, presents any symbol, which they truly believe to represent the power of Light and Goodness, their very belief will manifest itself in a force sufficient to drive away the undead."

So I think by proxy and logic you can't be a vampire