[Harzbahn 1873] Acquiring another players mine is giving "undefined method corporation? for nil"

[physic]

hotseat file:
https://gist.github.com/physic/a073b0b9f5fe200fb77a4bd09556b154

console error
https://gist.github.com/physic/04bff69e8e7c4b62dfa3bf342af40fb5

Steps:
Show mines from other players.
Select a price for the 8.
Purchase.
Confirm consent of the other player.
==> console error

I am blocked from making the purchase.

[roseundy]

Wow. Finally had time to debug this. Apparently, nobody had done a cross-player mine purchase before (or at least reported the bug when they tried) :-/