Help: How 2 use navigation with hands-free bluetooth

[srooks]

I'm trying to use Nokia Maps 2.0 with navigation in a car with built in hands-free bluetooth.
When the car pairs with the phone, all navigation prompts appear to be absorbed by the hands-free ..

Anyone know how to setup the phone such that calls goto the hands-free, yet normal audio prompts are delivered by the phones itself?

thanks,

steve