Split Poland with Soviets

[Scorn]

Playing as historically accurate Germans from 1936 and with the M&R Pact, how do I split Poland with the Soviets after triggering the Danzig or War Focus?

Playing this in different way I can't get the option to split Poland,or even get the Soviets to join the war at the same time. Does anyone know what needs to be completed to trigger the carving up of Poland?

[MachoWoman]

after you make poland capitulate an event will pop up giving you the chance to backstab Stalin or give him eastern poland

[Scorn]

Thanks a lot, I am not a patient man :|