for me upgrading the eventcalendar to 3.1.1 fixed the wp_post2cat error messages. see http://wpcal.firetree.net/2007/09/30/v311-release-candidate-2/
FYI:
Update on Simple Tagging Plugin v1.7… the plug-in is now being succeeded by Simple Tags 1.0.1 written by the same author as the Simple Tagging Plugin
http://www.herewithme.fr/wordpress-plugins/simple-tags
Got this error with the Google sitemaps too (2.7.1), deactivated and it appears to be working now..
I did the same thing as Jaffo. However, I uploaded and activated the 3.0 version of Google Sitemaps and it appears to have corrected my problem. However, this raises another question and thought:
Why did the plugins page not notify me of the new revision of Google Sitemaps (2.7.1 to 3.0) when I started to reactivate plugins after installing WordPress 2.3? Many other plugins did notify me of updates available for download and installation/
uh I regret found this page 2 replies 😀
because just deactive Google Sitemap Plugins was resolved all that error …I spend 2 days tried to fix that before 😀
many thanks
OMG I love you guys so much! I was about to choke on my coffee and commit suicide when I saw this stupid error. I hate doing upgrades for these reasons and crossed my finger nothing happen when I upgraded. Thanks a lot!
FYI:… it was the google sitemap v3.0b7 that caused my problem.