fakee

AcountProvider provider = AccountProvider.CreateProvider();
AcountProvider outProvider;
A.CallTo(() => mockAppointment.GetAccountCollection().GetProviderImpl(out outProvider)) // GetProviderImpl is a generic method
  .Returns(true)
  .AssignsOutAndRefParameters(provider);

bool result = mockAppointment.GetAccountCollection().GetProviderImp(out outProvider); // this returns false and provider is null???

No probs.

I remember the details now. This is actually by design. Unconfigured fake methods return a new instance each time and unconfigured fake properties return the same instance each time. Excruciating detail can be found in this conversation FakeItEasy/FakeItEasy#156