I just rewrote my very large thread for the second time, and when I posted it, I got a "You are not logged in!" message. I was.
The first time I tried to post it, I got an error too.
Something has to be done. Prehaps username/password verification when your posting it, incase you dont want to be logged out, or prehaps instead of a new page with the message, it appears under the edit window.
Please do something!