To update this (ancient) thread I had the same problem on my 2001 E430T coming back from Cornwall last week.
About 1hr into our journey the ABS/BAS lights came on so I pulled into the next lay-by perhaps expecting a puncture to have triggered the ABS sensor. A visual tyre check confirmed no obvious puncture and the brake lights were working as normal. I went to restart the car to continue the journey home but the engine would not turn over, ignition lights etc were fine but I then noted that the gear lever was locked in Park. I checked the fuses I knew about in the engine (main fusebox), dashboard (end panel) and under the rear seat but found them all OK. Out of ideas I called the RAC.
The RAC chap performed the same brakelight switch and fuse checks before checking against his portable (laptop PC) fault database. He found a similar fault previously recorded by a colleague where the ECU fan fuse (10A), located in the large plastic box on the other side of the engine bay to the main fuse box, had blown. He checked, it had! He replaced the fuse and the car started first time. He gave me a few spare fuses to try to ensure I could get the 200 miles to home but the car made it without further incident. It has also been fine since.
So was this ECU fan fuse failure related to the ABS/BAS error or completely co-incidental?
Cheers
Mark