Adv Guestbook 2.3.1 - Admin Password Problem - repeats login

I updated my guestbook to v 2.3.1 and now when I log into the admin area it accepts my password BUT as soon as I click a function I'm taken back to the username/password screen again. A loop.

I think I saw this problem listed here yesterday when I was having problems with the upgrade, but now I'm having no luck finding the thread. I tried copying/pasting the default password into that p'word field thru sql myadmin but I still get the same looping login routine.

Any help is appreciated.
Thanks,
Jack

This is the thread you want.
http://proxy2.de/forum/viewtopic.php?t=2595

That resetting of the password doesn't work, but one thread suggested replacing the 2.3.1 file - session.class.php - with the 2.2 version. I did this and it worked. I thought everything was fine until...

On one of my other domains, I deleted the 2.2, installed 2.3.1 and was all set to copy the session.class.php from 2.2 over the 2.3.1 version to cure the problem, BUT now that fix doesn't work! I've tried changing the password to the default and I'm still stuck in the admin loop. I even grabbed another 2.2 copy of that file and copied it over the 2.3.1 version and still, I'm stuck in the loop. argh!

Thanks for any help,
-Jack