Dammit.. How to get 2 zones and power from a 4-conductor

[Nelson Muntz <none@xxxxxxxxx>]

So I just finished this job with 5 home-run motions to the CP.  As I
was doing training I told him about the tamper switches on the motions
IS25100TC (front and back) that I wired in series with the alarm
contacts.  He thought that was great - then added, "so I'll be able to
know right away when someone knocks the thing off the wall, right?".
Of course the answer is 'no'.  I never planned on putting the tampers
on a separate 24 hour zone - otherwise I would have run 6 conductor.
Now he wants that "feature", and the trick for sharing a 'common' wire
for power and zone won't work as far as I can tell.  Am I correct, or
is there a way to do it without running more wire?