My belief is that it is a cookie setting from thoses sites that is causing the issues. They can set the cookie to expire after a length of time, and perhaps it's too short. Because they are not true database forums, the cookies could store incorrect information which may not be retained. Try another browser, like Mozilla, and see if you still get this error. I think you will. If you do, it's all them. If not, we need to investigate this further.
PS, if we solve this, you owe us to hang out and chat here.
