On the Xebee blog there's a recent post looking at test-driven development with the Zend Framework and PHPUnit. They show how they work well together and make it simpler to use TTD to create and test your applications.

Over the past few days I was going through the Zend Framework reference docs and I found myself pleasantly surprised with all that the latest version of this web application framework provides. [...] Out of the many new features, what stood out for me was the ease with which Zend Framework and PHPUnit complement and work with each other.

He talks about some of the features of PHPUnit (including dependencies, testing for exceptions and errors) and how it fits into a good deployment strategy. He shows how you can use the Zend_Test component of the framework, along with the Zend_Test_PHPUnit features, to make a sample test case. There's also an example of using the Zend_Test_PHPUnit_Db component to test database information and your backend data stores to compare them to a formatted XML document.