Command count requires authentication

[thisispax]

I'm trying to connect to a mongodb in the configuration of elastica as a driver.

persistence:
    driver: mongodb
    model: Some\Model

Mongodb is already successfully configured and used with the DoctrineMongoDBBundle. I thought the ElasticaBunlde will use these configuration to establish a connection to mongodb. Isn't it?

All I get ist this excaption:

In Count.php line 176:
                                         
  command count requires authentication

Edit: With disabled authantication in mongodb it all works finde