RPM - It would seem to me that a fair percentage of the Crossfires sold here were made the year before the model year that they are. The 10th digit of the vin as you said is the model year of the car, that's always the case.
My '05 Ltd has a 5 in that position but was built a year earlier as per the build sticker on the door jam. Most of the Crossfires I've looked at are like this.
My point here is be careful what you are getting, always check the vin and the build date. I work in the insurance business and I see a fair amount of people that buy what they thought were the new model year only to get last year's model. BE CAREFUL.

Pat