I upgraded a few of my websites this morning and suffered the WSOD (white screen of death).
As I used the automatic upgrade to Wordpress 2.8 both the website and the admin panel went blank.
I looked in my error log files and saw this line:
PHP Fatal error: Call to undefined method WordPress_Module::_weak_escape() in /var/www/vhosts/ …..
It seems the ‘Redirection’ plugin is at fault so do the following to sort out your Wordpress 2.8 upgrade.
1. Go in to the remote view of your files.
2. I renamed the Redirection folder to Redirection2
3. Voila. The Redirection plugin will be disabled and your blog should be working again.
4. You can then rename the folder back to its original version and update the Redirection plugin and then activate it again.
Hope this helps some people who are having the same problem on upgrading to Wordpress 2.8