Originally posted by linuss santoo: Is it true that only in the case of MDB u require the JMS? :roll:
In EJB 2.1 MDBs have been extented to support other messaging types beyond just JMS. However, it is true that in EJB 2.0 MDBs could only listen to JMS messages. Like it has already been alluded to, with the exception of MSMQ, all major MOM products support JMS. Therefore, it is usually not terribly difficult to get JMS running on top of the various MOM products. The only real difficulty exists in integrating these MOM products with your J2EE Server. However, since J2EE 1.3 requires the inclusion of JMS, it is usually unecessary to use external JMS Providers with today's J2EE Servers (there are still a few cases where external JMS Providers make sense).