I have this same problem in my categories.
I finally found this problem is:
I used a mysql db user that has not enough permission to upgrade my WP database.
I solved it this way:
1. get wordpress-2.0.2
2. change wordpress-2.0.2/wp-config.php, DB_USER=”root” (of course change its passwd)
3. use wordpress-2.0.2/wp-admin/upgrade.php, it will downgrade back to version 2.0.2’s DB.
4. change wordpress-2.2//wp-config.php, DB_USER=”root”
5. use wordpress-2.2/wp-admin/upgrade.php, everything is OK.
6. change back wp-config.php’s DB_USER.
have fun!
