Error when rendering DQL query

I'm using Doctrine with Symfony 2.1. Everything was working OK in Symfony 2.0 so I think I was using Doctrine 2.2. Now I'm using Doctrine 2.3-dev (packagist) and when I run the following query in a EntityRepository:

$em->createQuery('SELECT u, tc FROM XBundle:X tc JOIN tc.usuario u JOIN tc.tax t WHERE tc.timestamp >= :date_from AND tc.timestamp <= :date_to AND t.type = :x GROUP BY tc.usuario');

Nothing happens, getResult() just returns array(0){}

I've done \Doctrine\Common\Util\Debug::dump($query); and this is the result:

object(stdClass)#487 (18) {
  ["__CLASS__"]=>
  string(18) "Doctrine\ORM\Query"
  ["_state"]=>
  int(1)
  ["_dql"]=>
  string(180) "SELECT u, tc FROM XBundle:X tc JOIN tc.usuario u JOIN tc.tax t WHERE tc.timestamp >= :date_from AND tc.timestamp Marcos:project marcos$ 

As you can see something happens because the dql query got cropped and seems like Doctrine is not working properly...

If I change 'WHERE tc.timestamp >= :date_from AND tc.timestamp <= :date_to' for 'WHERE tc.timestamp BETWEEN :date_from AND :date_to', then the query is run without any problem and the debug dump function shows a complete debug of $query.