My dealer believes that they have fixed the battery discharge problem in my Z8. There is a service bulletin regarding a defective "compensator", (apparently a device that handles the electrical interface with the cell phone and CD changer). This time they found, if I remember correctly, a 400ma/hr drain when the car was shut off. The service bulletin also covered replacement of a wiring harness segment. Having completed both repairs this morning along with my 1200 mi service, they think I should be all set now.