Again, it is not recommended to shut down individual services except in the specific tasks as described in various parts of this manual. Certain services have dependencies on other services and must be started in a prescribed order. Complications can arise when trying to start services on their own. For this reason, you should start and stop all the services together using the start-msg and stop-msg commands.
The services must be enabled in order to stop or start them. See 18.104.22.168 To Specify What Services Can Be Started.
The start-msg and stop-msg command start and stop all of the MTA services, not just the SMTP server. If you want more granular control when starting or stopping the MTA services, you can use the start/stop-msg command for the dispatcher and the job controller. For more information, see start-msg in Sun Java System Messaging Server 6.3 Administration Reference and stop-msg in Sun Java System Messaging Server 6.3 Administration Reference.