I'm not sure if this is related to EZP or not, but the issue seemed to come up about the same time.
My users have complained about having to log in twice. Well, not actually log in. The first time they do it, from the box on the main screen, it comes back with 'incorrect password' error and throws up the screen with the main box to re-enter.
However, this is happening too much to be actual wrong passwords. There's a lot of them on the error log. I've had it too, but the strange thing is it doesnt' seem to happen every time. I'll go away and do a bit more research later, but just wondered if it related?