upgrading from WP 2.5RC1 to WP 2.5RC2 gave me following error:”

[client xx.xx.xx.xx] PHP Fatal error: Call to a member function on a non-object in /home/.sites/143/site2/web/wp-includes/taxonomy.php on line 165

Replacing the taxonomy.php (the 2.5RC1 version) and WordPress could be updated and It seens to work, but the new version of the taxonomy.php file cannot be used

update: removing the “simpletags” plugin solved the issue. No need for this plugin anymore from 2.3 to 2.5 as there is native ‘tag’ support within WordPress