All statics faked, but Isolator says they are not

We're still on version 5.2.3

This test is against code that uses Microsoft's Pattern & Practice UIP (User Interface Process) block.

The error from Isolator is:
*** Cannot use Isolate.Verify on a sattic method without first setting static method behavior using Isolate.Fake.StaticMethods().

The test is this:
[code]
Navigator navigator = Isolate.Fake.Instance<Navigator>(Members.ReturnRecursiveFakes);
DerivedController target = new DerivedController(navigator);

Isolate.WhenCalled(() => target.State["XYZ"]).WillReturn(new SomeObjectRequiredForMethodUnderTest());

target.MethodUnderTest();

Isolate.Verify.WasCalledWithExactArguments(() => target.State.Remove(target.SomeConstant));

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So first, State.Remove is an instance method, not a static method - I imagine it's something underlying though, so second, I fake static constructors and methods on both State and Navigator and no matter what I can't get this error to go away.

Any ideas? If the message included the name of the object that static methods needed to be faked on, that would make life a lot easier (or if it just went ahead and faked it for me).

Thanks, Brian