In a recent post Marcelo Gornstein takes a look at using dependency injection with Doctrine2 using his Ding container.

This article will show how we can develop software in php with a nifty design and architecture, and very much like other languages like java, using an ORM and an AOP, DI, Events container. I will assume you've read (or at least took a quick look) at this article that explains the tree layout used throughout the code, and that you have some basic knowledge of Doctrine2 and used it before on your own.

He starts with the result - an easy to use, self-contained (and decoupled) system for accessing the Doctrine2 instance. It's event-driven and uses Aspect-oriented programming to mange interactions between components (or as he calls them "beans"). Code is included for the entire process for a logger, the User entity, entity manager, user repository and transactional aspect. You can find the complete source for his example on his github account.