How to test Mollom - want to test mollom_form_moderation?

Question

I have a custom form that I'm protecting with Mollom. Once validated, the form results in an entity being created and some emails being sent.

If the form is valid, but Mollom says it should be moderated, I need the entity to be created with its "Held in moderation" field set, but no emails to be sent (I'll do this once an admin has said it's OK).

I have Mollom working and testing mode enabled. Putting "ham" in works. Putting "spam" in stops it dead. Putting "unsure" with an incorrect captcha stops it dead and putting "unsure" with a correct captcha allows it through.

I'm trying to find a test to make Mollom say "hold this in moderation" and call the moderation callback that I have set in hook_mollom_form_info(). None of the test cases above result in this callback being called.