if you really want to bang her, this is what you do...
don't be a douche... don't say anything about her being a pornstar right away... just go hang out with that dude and be cool about it... invite him and his girlfriend to parties n shit... get to know her, get her number, etc... then when they break up, give her a call...
if her being a pornstar gets brought up, just smile and casually acknowledge that you knew about it already and you thought it was pretty cool... again the key here is to not be a douche, even though you're probably really excited, just try to be zen about it...
Or pay her money to be in a porn with you.