Bob-Dubery
This has happened to me several times lately - but I didn't quite believe it until now.
You can be logged in and then
1) Log out
2) Go straight to "unread" (or try to) and be told that you have to be logged in to use that page. (which is fine)
3) Ditto with PMs
4) Then 10 minutes later, without logging in I find that I CAN get into those parts of the forum, even though the tool bar is offering me the option to log in.
To REALLY force a logout I have to clear cookies and everything else out of my browser cache. Which resolves the problem until the next time.