This seems to be the big disease right now, how come, has there been some new Zorro movie that inspires kids to go out looking for "weapons" ??
Anyway, I read that someone had an idea about adding a peace of metal to the rear door to make the engine door unable to open by itself . 
This sounds ugly to me!
Since you have to open the rear door anyway, wouldn�t it be easier or at least nicer to get a wire or stick down from above ?
I would think a hood or choke wire from the yard together with the kind of doorlock with  a spring that you sometimes use in stable boxdoors could do the job nicely if you don�t wanna be really hi-tech and use an electric trunk opener from some jap car, should be easy to find in the junkyard too

Calle

who don�t have these problems since all visible through the service door is the timingwheel and fanbelt of the Volvoengine :-)