Got your PM.
Installed latest Captcha 2.2.2 available for doc subscribers.
It seems to work ok during registrations (tested it once), but appears to have issues elsewhere.
I guess the caching is messing up sessions and breaking Captcha security.
I am not sure how related this is to exactly this problem. I am not using memcache (as far as I know), but if I use the cache plugin that comes with Joomla, captcha does not work on retry (refresh or subsequent attempts). What happens is that the text is regenerated, but the old image is presented. The user does not see the new image.
Is there a way of excluding captcha from cache?
I pulled this from joomla system info:
What php version? 5.2.13
what GD version? bundled (2.0.34 compatible)
what freetype version? 2.2.1
I was just wondering how to do it. I can't click on your picture or the name.