Spring MVC - Beans chargés deux fois

package com.example.config.db;

@Configuration
public class MongoDevConfig {

    private final static Logger logger = LoggerFactory.getLogger(MongoDevConfig.class);

    @Bean
    MongoDbFactory mongoDbFactory() throws Exception {

        logger.debug("Init...... MongoDbFactory() in production mode!");
        //...
        return new new SimpleMongoDbFactory(mongo, "db");;

    }

}

2015-03-05 17:52:32 DEBUG c.m.config.MongoLiveConfig - Init...... MongoDbFactory() in production mode!
2015-03-05 17:52:32 DEBUG c.m.config.MongoLiveConfig - Init...... MongoDbFactory() in production mode!