I don't know if it's a copyright violation or not. There's undoubtedly some
kind of licensing agreement that popped up when your friend downloaded the
OS or when he first ran it, and that agreement would be the first place to
look for an answer to your question. If Sun puts this OS out for anyone to
do with as they please, including modifying it and redistributing it, then
your friend is all right. But I'll bet that there is language in the
licensing agreement that addresses this issue. If the language is too
impenetrable for your friend, I'll have a look at it if you send it to me.