I have managed to resurrect my site and it looks like the hacks have been removed. Here is what I did (YMMV):
- Backed up the site files
- Backed up the database
- Created an environment for testing on my local machine using WAMP
- Restored my database to the local environment
- Unzipped a new copy of WordPress 2.8 to my local environment
- Modified my config files to point to the local database.
- Reinstalled my plugins and themes. At this point everything looked OK with no hacks in place.
- Deleted completely my old installation on my web host
- Uploaded my new installation
- Changed the config file over to contain the server DB connect parameters
- Deleted the active plugins value from the config table to remove references to the hacked plugin files
- Reenabled my plugins
- Switched the URL options to a different scheme and then back again to repopulate the page caches.
2 Important things to note: I lost all of my uploaded files and images. I didn’t want to take the risk of having a corrupted image file hanging around. Also this would not have worked if the data in my database had been altered to contain hacked pages.