I'm severely reworking the PHP version for some pretty tight integration with my site, and I just noticed something that I think is wrong. In your COPPA check in adduser.php, you check if $age == "no", and spit out an error if so. That's wrong, you should be checking if $age == "yes" and allowing them through if so. The way that things are set up right now, a user could simply not answer the question and be admitted, which isn't exactly COPPA-compliant. I changed my copy, you might want to change the master too. Don't know if the Perl version reflects this same problem or not.