Here's an example:

```php
<?php

namespace MyModule;

class Module
{
    public function getServiceConfig()
    {
        return array(
            'initializers' => array(
                'my_orm_initializer' => new DoctrineModule\Service\ObjectManagerInitializer(
                    'Doctrine\ORM\EntityManager'
                ),
            ),
        );
    }
}
```