Unlike earlier bikes the immobiliser for the 848,1098,1198 sits within the speedo not the ECU.
Possible water ingress on the connector to the speedo or even to the antenna around the ignition lock?
I have read about water being trapped between the antenna and the plastic shroud stopping the key being read. Drying it all off cured it. http://www.ducati.org/forums/1098-11...zer-error.html