Compatability with the newst version of Java?

I've been having trouble with mafia lately. I'm wondering if it's compatible with the most recent Java update (Version 6 Update 18)? When I try to log into mafia it acts like it's going to sign in normally but then doesn't come up with either the relay browser or the usual interface and it causes my computer to freeze until I force Java to close.

edit: This occurs with both the .exe version and every .jar file I've tried.