I have hair that's a little bit above shoulder length, and I don't pass at all (My hair is probably not the biggest problem there, though, because my face is very soft and round looking). Also, the bottom of my hair has a really annoying tendency to flip outwards, which makes it look even more feminine. =_=
I'd wear my hair shorter, but I don't think it would look good on me, and so I'm a bit afraid to try it.
I think the trick to long hair is finding haircuts that highlight masculine features of your face. It can be kinda tough, but if you do some research on longer guy's hairstyles, you might get somewhere.
Just keep in mind that for some guys, passing with long hair is harder, and for some guys, passing with short hair is harder. All depends on what you look like.