Thanks Mike, I was hoping this was the case.
I have asked my MB dealership to price the kit and installation for me. For now I am happy to plug my shuffle into the connector, but I can see that for longer trips (in the outback

) that being able to use the steering wheel controls to find songs etc would be great.
For me getting the interface kit will mean needing to upgrade my Ipod also, as I am currently quite happy with my tiny little shuffle.
I actually do live in a rural area, about 20km from closest town, but not quite classed as outback where we are!
Many thanks, cheers.