Other threads about same problem:

http://discussions.europe.nokia.com/...ighlight/false

http://discussions.europe.nokia.com/...e/td-p/1190499

Some seem to have locked their telephone by accident - some (like me) have experienced that the phone locks itself upon a change in the MfE account setting. In my case I changed the server-name, and that was the last I ever did on that device.