[Zope] Product unable to be called

A coworker and I developed a product for our customers handling minimal content management, and the mangement side works pretty flawlessly. We can add new content items, edit them, etc. But now, when we go to publish them, I'm getting errors about __call__ not being found. We used the Boring Product tutorial as our guide, and it never mentions making a __call__ method in the Product's Class definition, so we never did. I see that many other Objects use __call__, but I'm not sure where to proceed with ours. Any pointers? Zachery Bir <zbir@urbanape.com> <URL:http://www.urbanape.com/>