Has anyone out there added a Bluetooth car kit to their non-BT 04 or 05 Prius? I've seen a number, ranging to a speakerphone type set up from Jabra, to a more-advanced system from Sony Ericsson and other vendors that use the car's speakers. Wondering if anyone has had any luck using these, or any other experience to report on it? Getting one installed and running would seem to be a much easier way of getting Bluetooth than selling my 04 Canadian B packag for a 05 C package, which adds BT and Nav.