What care must be taken when multi-threading JMS clients?
The JavaSoft JMS specification version 1.0.2 states that JMS sessions are single-threaded. Consequently, if multiple threads simultaneously access a session or one of its consumers or producers the resulting behavior is undefined. In addition, if multiple asynchronous consumers exist on a session, messages will be delivered to them in series and not in parallel. To take advantage of multiple threads with JMS, use multiple sessions. For example, to allow parallel synchronous receive requests, design the application so that only one consumer may be active per session and use multiple sessions.
