I found myself having to reteach myself the Zend Framework 2 DI system this week.
This is a great quick start to get the development environment running.
http://ocramius.github.io/blog/zend-framework-2-controllers-and-dependency-injection-with-zend-di/
And for production it's better to use factories.
http://www.zfdaily.com/2012/07/getting-dependencies-into-zf2-controllers/