5.2.5. Message-driven beans

Message-driven beans can function as Seam components. However, their call method differs from that of other Seam components — rather than being invoked with the context variable, they listen for messages sent to JMS queues or topics.
Message-driven beans cannot be bound to Seam contexts, nor can they access the session or conversation state of their caller. However, they do support bijection and some other Seam functionality.
Message-driven beans are never instantiated by the application; they are instantiated by the EJB container when a message is received.