It will happen to me every now and then. I'll log in, read the other forums, and then have to re-log back in when I click on the classifieds. Computers can be so much fun!
It's happened to me a lot. I sent an message to the staff a couple of weeks ago but haven't heard anything back. I understand having to re-log in if you haven't done anything for an hour. But just going between forums, I had to re-log in 7 times last Saturday and 6 times on Sunday.