Right now, letters in CAPTCHA images all have to be typed in the correct case or they won't be recognized. Since there are never any lowercase characters anyway (as far as I know), it doesn't help against bots and just makes it harder for humans to enter the correct code, so why not remove the requirement?

There are lowercase letters...I've seen several.

Are you sure? I just checked my registration page and I didn't see a single lowercase letter there after ~20 refreshs. Either I'm incredibly lucky or there are only uppercase letters.

http://forums.invisionpower.com/index.php?showtopic=235441
http://forums.invisionpower.com/index.php?showtopic=234324

Just from a quick search of "captcha"

Whoops, sorry. But when there are so many threads about it, why haven't you guys done anything yet? ;)

It wouldn't be too complicated to throw a strtoupper in there somewhere, would it?

There are hundreds of duplicate suggestions - doesn't mean we necessarily have the time and resources to implement each one. :P

I've already replied to one of those threads - I agree with the general suggestion. That doesn't mean, however, it will make it into a minor point release.