Ok, now the one million dollar question. Why did the sessions table become corrupted? On my site it gets corrupted twice a day, so continually flushing it really isn't an option.

From what I've gathered, the cause of my sessions table becoming repeatedly corrupted has to do with a different collation character set in the database then what XOOPS is inserting.
.. from phpmyadmin main page...
Server version: 5.0.45-community-log
Protocol version: 10
MySQL charset: UTF-8 Unicode (utf8)

But I see the actual collation on the XOOPS tables is different latin_swedish_ci I think

I was going to do a MySQL dump of the whole XOOPS database, I would then adit out any character set parameters from the MySQL dump and restore it..

But ! Before I totally break my site, or possibly waste lots of time, could someone in the know tell me if that even has a remote chance of solving this once and for all ?

I presume I'd also need to edit the MySQL class file, and add the character set mysqlquery lines I found elsewhere on the forums, to ensure XOOPS always speaks UTF8 to mysql

I had the same thing all of a sudden. Since I couldn't get to the admin panel, I disabled the site by editing the config table directly via phpmyadmin. Then I went to flush the sessions table, and PHPMyadmin says that table is damaged so I flushed it anyways and now everything works again !!!!! YEAH !