Ditto. I am getting the same message. I get this message when I activate a plugin. The plugin does activate, however. I go back in the browser, reload the plug-ins page, and it’s there, active.
Repairing my database doesn’t help.
Tried dropping the database and starting from scratch. It seemed like I didn’t get the error until I activated the wordpress.com stats plugin, but after doing that, the error persisted on all plugins, even after I deactivated the stats plugin.
Note, I am running this site in a local developing environment using MAMP.