Fatal error after upgrading to 3.0.1

I’ve read that a few people have had this same issue. After upgrading I received this error:

Fatal error: Call to a member function add_rewrite_tag() on a non-object in /home/bartend3/public_html/wp-includes/taxonomy.php on line 289

I’ve tried renaming the plugins folder and I’ve disabled all plugins through phpmyadmin but I’m still getting the error. Any suggestions would be greatly appreciated. I need this site up ASAP.

The plugins I’m using are:

– Akismet
– Contact Form 7
– BuddyPress
– Page Restrict
– WP E-commerce
– Sidebar Login

I’m pretty sure WP E-commerce is the plugin that caused the problem but I removed it and disabled all plugins but I’m still seeing the error.

Any ideas? Thanks.