This seems to happen quite a bit on some new cars, and is probably due to a faulty sensor. If you check this Technical section you will find similar faults and different solutions. In most cases it's a hook-up to the diagnostic computer to see which sensor is playing up and what repair is required and the job is done.
Don't let it put you off, it can happen to any new car! I saw a BMW X6 stopped on the motorway with the hood up last week!
Cheers!