hello,
i posted a rough demonstration of how to connect an arduinoBT board to a symbian based S60 mobile phone here: http://www.arduino.cc/playground/Code/SymbianS60Python
with no changes (only put the right bluetooth address into the script) the same python code can be used to connect the phone to a comport object in pd (or any other software capable of opening a BT serial port).
the python code is horrible but i hope some of you will improve it and post it back for further use.
best