title: How to configure doctrine extensions in Zend Framework 2?
body: <p>I have added this line to my composer.json:</p>
  
  <pre><code>"gedmo/doctrine-extensions": "dev-master"
  </code></pre>
  
  <p>And this is inside my module's module.config.php:</p>
  
  <pre><code>'doctrine' =&gt; array(
      'driver' =&gt; array(
          __NAMESPACE__ . '_driver' =&gt; array(
              'class' =&gt; 'Doctrine\ORM\Mapping\Driver\AnnotationDriver',
              'cache' =&gt; 'array',
              'paths' =&gt; array(__DIR__ . '/../src/' . __NAMESPACE__ . '/Entity'),
          ),
          'orm_default' =&gt; array(
              'drivers' =&gt; array(
                  __NAMESPACE__ . '\Entity' =&gt; __NAMESPACE__ . '_driver'
              ),
          ),
      ),
  ),
  </code></pre>
  
  <p>Then I want to use timestampable annotaion in my entities, for example:</p>
  
  <pre><code>/**
   * @Gedmo\Timestampable(on="create")
   * @ORM\Column(type="datetime",nullable=true)
   */
  private $created;
  
  /**
   * @Gedmo\Timestampable(on="update")
   * @ORM\Column(type="datetime",nullable=true)
   */
  private $updated;
  </code></pre>
  
  <p>But that doesn't work. When I persist the entity with above annotations, the created and updated columns are NULL.</p>