It sounds as though the cookie for the rest of the site either didn't get set or has expired. Try logging out of the forum and then logging back in. You might also double-check your browser's cookie settings, lthough if you've stayed logged in on the forum they are probably ok.
Hopefully logging out and back in will clear up the problem. Please let me know if you continue to have a problem with it. (I tested the feature with my regular user persona and didn't have any problems, so you
shouldn't either, but we all know how
that is; computers can be such ornery things sometimes.)