OK I've tried pretty much everything I've seen in the posts here. Clearing cookies, using dbsessions, etc. There's got to be a better solution that will actually last a few minutes. Is Moodle 1.8 really that much of a mess. I ran 1.5 all last school year without a hitch. I thought "upgrading" to 1.8 would be just the ticket for more powerful user management. It's turning out to be a royal pain in the backside and my teachers are starting to look at me with cannibalistic glints in their eyes.
"A server error that affects your login session was detected. Please login again or restart your browser." is driving us crazy.
Developers, is there an answer? I've still got 1.5 up and running but would rather move on to the "better and more wonderful" version 1.8.