SQL Logger in Doctrine 2 ORM and ZF2

quick-doctrine-orm-zf2-sql-logging.local.php

<?php

use Zend\ServiceManager\ServiceLocatorInterface;

return [
    'service_manager' => [
        'delegator' => [
            'doctrine.entitymanager.orm_default' => [
                function (ServiceLocatorInterface $sl, $name, $requestedName, $callback) {
                    /* @var $em \Doctrine\ORM\EntityManager */
                    $em = $callback();

                    $em->getConnection()->getConfiguration()->setSQLLogger(new \Doctrine\DBAL\Logging\EchoSQLLogger());
                    
                    return $em;
                },
            ],
        ],
    ],
];

I had to change from delegator to delegators to work.