adds anti-spambot measure to user registration

Gaaaaak! Since some spammer has decided to use a robot to create bogus user accounts on, we've added a new security feature to our account creation page. Spammers would make pretty good trebuchet ammunition, wouldn't they?

The new user registration screen (which you can only access if you are not logged in) now has a feature called a "captcha", which displays a graphic with some text in a wavy line on it. To create an account, you now must retype that text. The theory is that a human eye can easily read the text, but a spambot cannot. In practice, a smart spambot with optical character recognition (OCR) can read the text, so the system isn't foolproof. It does, however, make it a little more difficult for the spammers.

If you are already logged in with a personal account, you won't see the extra verification because you have already proven your identity to the system. Also, this new feature does not affect your existing registration -- you don't need to re-create your account.

There is a problem with early Firefox versions and possibly with a few other browsers, that causes the verification to fail even if you properly retype the text. Fortunately, there is an easy workaround to this problem (which is a browser bug, and not something we can fix). Just click on the verification image to display it on a page by itself, then use the browser's back button to return to the form, and everything should work for you. At worst case, email the webmaster and we'll create your account for you manually if you can't make the form work.

We're sorry for the inconvenience to our new users. We took this step reluctantly, only after actually being hit by a spambot. We are currently looking for authentically medieval ways of dealing with the problem of spammers, and are considering options ranging from rotting meat in their wells to sappers under their castle walls. "Hey spammer, nice village ya got there. Shame if it got infested with plague rats, huh?"