title: Doctrine 2.1 - datetime column default value
body: <p>Could someone tell me how to add the default value on a DateTime column? I can't do it like this:</p>
  <pre><code>protected $registration_date = date(&quot;Y-m-d H:i:s&quot;, time());
  </code></pre>
  <p>So how can I handle it?</p>