title: Symfony 2.3 / FOS User Bundle duplicate definition of column
body: <p>We use FOSUserBundle with Doctrine and need to change the mapping. The following approach worked fine wth Symfony 2.1.x:</p>
  
  <ol>
  <li>Our User-Entity extends FOS\UserBundle\Model\User</li>
  <li>Our mapping.orm.yml maps all fields used by the bundle</li>
  </ol>
  
  <p>This is still the recommended approach (<a href="https://github.com/FriendsOfSymfony/FOSUserBundle/blob/master/Resources/doc/doctrine.md" rel="nofollow">https://github.com/FriendsOfSymfony/FOSUserBundle/blob/master/Resources/doc/doctrine.md</a>)</p>
  
  <p>After upgrade to Symfony 2.3 this no longer works: the update "doctrine:schema:update --force" yields errors of the type </p>
  
  <p>duplicate definition of column "x"</p>
  
  <p>where x is any field already used by FOSUserBundle.</p>
  
  <p>Does anybody know which changes cause this error?</p>