We had some issues the last weeks with the forum, but i'd hoped this was solved by now (as we've been told by our sysadmins). Are you still today facing this issue? Do you still need to reset it every time you want to log in?
Can you try again and let us know if it's still happening. We have to have spam and attack protection, which may be causing the problem. We've turned on extra logging, so that might help show us what's going wrong if it keeps happening.