Problems stubbing return values for 'out' parameters

[TestFixture]
public class TypeMockTest
{
    [Test]
    public void Test()
    {
        //set up expectations
        OutParameter stubReturnValue = new OutParameter("2");
        OutParameter supplied = null ;
        Mock stubbedClassMock = MockManager.Mock(typeof(StubbedClass));
        stubbedClassMock.ExpectAndReturn("StubbedMethod", stubReturnValue).Args("ignored", new Assign(supplied));
        //perform the test
        ClassUnderTest classUnderTest = new ClassUnderTest();
        string actual = classUnderTest.Call(new StubbedClass());
        Assert.AreEqual(stubReturnValue.value + "1", actual);
    }
}

public class ClassUnderTest
{
    public string Call(StubbedClass ctlr)
    {
        OutParameter returnValue;
        ctlr.StubbedMethod("ignored", out returnValue);
        return returnValue.value + "1";
    }
}

public class StubbedClass
{

    public void StubbedMethod(string param1, out OutParameter outparam)
    {
        outparam = new OutParameter("2");
    }
}

public class OutParameter
{
    public string value;
    public OutParameter(string value)
    {
        this.value = value;
    }
}

TestCase 'TestSolution.TypeMockTest.Test'
failed: TypeMock.TypeMockException : 
*** No method StubbedMethod in type TestSolution.StubbedClass returns TestSolution.OutParameter
   at TypeMock.Mock.a(String A_0, Object A_1, Boolean A_2, Boolean A_3, Int32 A_4, Type[] A_5)
   at TypeMock.Mock.ExpectAndReturn(String method, Object ret, Int32 timesToRun, Type[] genericTypes)
   at TypeMock.Mock.ExpectAndReturn(String method, Object ret, Type[] genericTypes)
   D:TestSolutionTypeMockTests.cs(56,0): at TestSolution.TypeMockTest.Test()