Ok I'll start by saying I've been on a Jailbreak rant, and still have some strong ideas about the ethics of it at minimum on doing it. Now to the point. Darwin forms the core set of components upon which Mac OS X, Apple TV, and iPhone OS are based. It is compatible with the Single UNIX Specification version 3 (SUSv3) and POSIX UNIX applications and utilities. Now since iPhone OS is based on Darwin and Darwin is open source aren't you allowed to make changes to the open source components. I know the apple original work would be excluded but the rest would seem fair game. I'm sure this is how Jailbreak got in to begin with. Does anyone know if Jailbreak only modifies the open source components in iPhone OS and adds new software, or are they modifying original Apple work. I think so long as they are only changing the open source they are not violating any copyrights of Apple. Just a thought but if anyone knows I'd like to see it for myself so post a link to your source.