[Suicide Junkie]

Its just a simple double-hull idea.

If the water dosen't vaccuum-freeze fast enough to block the hole, you could always pour goop in to make it self-sealing.

Puncture-sealing fluids are advertised all the time these days, for car tires and radiators and whatnot... Just buy some in bulk from Canadian Tire.

If all else fails, pour jello into the outer hull. You could even make the jello armor piece by piece, so you don't have to build the entire outer hull, just a mold for while the jello sets.