I suppose...
This only works with the mechanical levers, not the newer boxsters with trunk release buttons.(I posted it on pg1 of this thread, but didn't realize the op had the buttons).
Simply remove fuse C3 and use a wire to apply +12v to the fuses terminal. This will release the lever lock. Pull up on lever...voila!
I've heard that a regular, small 9 volt battery is powerful enough, but have never tried one.