"Does it say that in the GPL somewhere?". Damn you guys. Just read the GPL2. If you use it and deliver it and modify it then you have to reveal what you did with the original code. And that is it, how damned difficult is that to understand. If you don't like it use BSD like Apple, take it and do what ever you like with it. Kids commenting, nothing wrong with kids, i have three, but just read the GPL before you comment, it's not that difficult after all.