Much has been written on Dependency Injection lately [...]. Its an awesome pattern if used on a larger scale and can (re-) wire a complex business application according to a clients needs without having to change much of the domain code. Beginning with version 1.8 Zend Framework is able to integrate any of these DI containers into its Zend_Application component easily.
He gives an example of this integration, adding in the creation of the container as a part of the bootstrap setup (a getContainer call on the front controller object). He also introduces the Yadif DI container (a lightweight container written by Thomas McKelvey) and how to set it up including its own configuration file.