I failed last night in my efforts to set up phpBB on Inkstain (Nora and her friends want a bulletin board) because of a PHP version mismatch. The suggestion on the PHP site - upgrade your PHP - is not an option. So I'm looking for a good GPLish alternative. Any suggestions (keeping in mind the jfleck motto - "I do not want to be a hacker.")? The main thing the kids seem to need is threaded discussion.