Hi
The problem here is that only the first call to myMethod is mocked
so the argument checker is not called the second time.
To mock and check arguments on all calls Use:
mock.ExpectAlways( "myMethod").Args( new ParameterCheckerEx( Check ) );
To mock and check arguments only n times (2 times in this example) use:
mock.ExpectCall( "myMethod", 2 ).Args( new ParameterCheckerEx( Check ) );
Hope it helps.