@Test
  public void testExecValidate() throws Exception {
    BEANS.get(IExtensionRegistry.class).register(NameFieldExtension.class, NameField.class);

    MyForm myForm = new MyForm();
    myForm.start();
    NameField nameField = myForm.getNameField();
    nameField.getUIFacade().parseAndSetValueFromUI("hans");
    Assert.assertNull(nameField.getErrorStatus());

    nameField.getUIFacade().parseAndSetValueFromUI("bernd");
    Assert.assertNotNull(nameField.getErrorStatus());

    nameField.getUIFacade().parseAndSetValueFromUI("berndExtension");
    Assert.assertNotNull(nameField.getErrorStatus());
  }