Using a repository with composite keys generates invalid SQL

Invalid SQL is generated when using composite keys along with Repository methods (fineOneBy, etc). Everything works properly when using createQuery() to generate DQL manually.

Working:
$q = $this->_em
->createQuery(
"SELECT c,c2,g FROM Entity\OAuth\Consumer c LEFT JOIN c.group g LEFT JOIN c.clinic c2 WHERE c.key = '{$consumer_key}'");
$this->_consumer = $q->getSingleResult();

Invalid:
$this->_consumer = $this->_em->getRepository('Entity\OAuth\Consumer')
->findOneBy(array('key' => $consumer_key));

Generated SQL for "invalid" method:
SELECT ... FROM oauth_consumer t0 LEFT JOIN groop t10 ON t0.groupId = t10.id LEFT JOIN company t17 ON t0.companyId = t17.id LEFT JOIN clinic t28 ON t0.dsid = t28.dsid t0.rid = t28.rid LEFT JOIN user t50 ON t0.userId = t50.id WHERE t0.`key` = ?

Notice the missing AND in the query above. I've attached the entities in question.