My Passat was broken into like this. The wiring for the windows on the back of the barrel lock are used to unlock the car.
There was an investigation done by BBC Watchdog a few years ago about this problem.
You have th option of going to the dealer where they can fit a replacement door handle which blanks over the barrel lock.
This means you can only open / close the doors usign the remote.
Speak to your nearest dealer or to VW Customer services UK about this. All the dealers were made aware of this 'modification'
This applies to Passat / Mk4 Golf and New Beetle, possibly other models...
