Over at the Jabber.org IM service, we have turned off the technology we've long used for account creation, called in-band registration. The security problems associated with unprotected in-band registration have simply become too serious for us to continue using it. I hope that eventually we'll be able to deploy CAPTCHA forms with in-band registration, but for now we're using web registration (including CAPTCHAs) via the web at register.jabber.org.
Oh, and lest I forget: many, many thanks to Matthew Wild for his help in migrating to the new system!
Peter Saint-Andre > Journal