MDACIII speakerphone & handsfree

[Guest MarkBR]

I'm looking for a bit of advice here ...

I have an MDA Compact III with Tom Tom Navigator 5, which I now use in the car combined with a holder and car charger. The sat nav element is great, especially turning the unit to landscape mode. The problem is receiving calls.....

There is a phone option to auto answer after a chosen number of rings, but switching to speaker phone seems to be manual option that has to be pressed for each call. Is there some way to leave the unit in speakerphone mode? (nothing in the manual).

There also seems to be a Phone option of 'handsfree', but this seems to be always greyed out on my unit; again nothing in the manual about it. Anyone know what this does and how to invoke it?

I know a Bluetooth headset is one obvious solution, but has anyone found a workable way of taking calls in a car without this?

Thanks

(ps reason I hesitate about the bluetooth headset is that this unit is capable of using a stereo headset which would be good for listening to MP3s but needs a bit more investigation!).