As many of you may have noticed over the last few weeks, the "captcha" system used by phpBB to prevent spam bots from registering at the forums has been exploited - the name of the offending bot is
Xrumer - a windows application that can be used to totally fill a board with crap users and messages.. it even employs the use of proxies to avoid ban.
In order to resolve this issue, I have replaced captcha with
recaptcha 1.10 by
Carnegie Mellon University.
So far it seems to be behaving well - not only does it look a little better, their words are relatively easy to read. It uses a private/public key specific to our domain, and as a project of a university, it also doubles to digitize books by utilizing the humans that are reading the captchas as a manual, world contribution to assisting the automated OCR of old books into digital form - that's right - each time you read a captcha, you are helping increase the amount of digitized books in the world.
Let me know if you hear any reports of people having difficulty registering.