Perhaps the mounts are physically identical but the contacts and electronics might not be the same.
The contacts are identical as well. Both have loads of plastic and flex wires inside (lot more than real glass, I think)- so no big difference there either.
I opened the 14-42 kitzoom for an experiment and discovered an extra (free) screw inside. Left there like an extra button for a shirt or a jacket!
One notable difference (that I know) between Pany and Oly is this:
Pany puts a very thin O-ring to seal the mount (sort of a weather seal). Screws are screwed straight through the mount holes and into the plastic slots inside the lens.
Oly lacks the O-ring but the metal mount covers (and seals) the lens. The screws are screwed through the mount's hole and through tiny brass shims before hitting the plastic grooves. This sort of cushions the mount. Old fashioned but effective.