Unswitched 12V socket?

[newboy]

We go camping a lot, and one thing we like to do in the evenings is to hook up a fluorescent reading lamp - just 12 watts or so - to the 12 socket in the car. Except that, on my new B6 (2007), all the sockets seem to only work when the ignition's on. I think this is the first car I've ever had where they've limited it in this way.

I'm not too cack-handed when it comes to fixing up this sort of thing. Is there any way that I could, for example, re-route the socket in the rear load space to an unswitched 12V power source?

Thanks

newboy