On the PHP::Impact blog today Federico takes a look at the history of using models in components within the Zend Framework:

More and more users are finding it difficult to load models within Zend Framework modules. This is strange, considering that modularity is an important design principle and its goal is to design systems that are easier to extend, understand, design and manage.

He brings in quotes and examples from different developers' blogs talking about their use and brings it up to the present day with an example of using a Zend_Module_Front controller with a Zend_Module_Action in a simple example of a module-specifc method for using a model.