can my bluetooth pda connect to my bluetooth cell phone as a speaker?

Hi, can my bluetooth pda connect to my bluetooth cell phone as a speaker? i
want to connect the audio output jack of my pda directly into my car
stereo's audio. then i want my bluetooth cell phone to connect to my pda so
that i can hear the phone conversation over my car stereo speakers. also, i
can hear my pda's gps audio prompts and music from my ipaq. p.s. i have an
ipaq 3870 and a nokia 6230 cell phone.