UBB.Developers Forums UBB.threads 7 Development How Do I? add more registration fields?

i want to be able to add a couple more fields to the registration form (since right now anyone can just register, no questions asked). i want the ability to have a couple custom fields where i can ask new people to fill in some more info, other than username and email. ubb classic has this feature, but it seems to be absent in ubb.threads

thanks!