I have a requirement where in we are migrating from WAS 4.x to 5.1. In-order to remove threads in EJB which is present in the current code, i came up with the idea of using Timer Service in EJB 2.1. However i'm not sure whether EJB 2.1 is supported in WAS 5.1.x. If any one knows, do let me know.
Also, is there a way i can remove threads in EJB using MDB's and JMS ? The current code uses threads for scheduling jobs. (I cannot use third party vendor's like quartz for implementing schedulers in my application :-().
I don't think WAS supports EJB 2.1 until version 6. Using JMS and MDBs are good for firing off asynchronous tasks, but it doesn't really work well for scheduled tasks.
We are on 5.1 and have left most of our quartz like tasks in the code. WAS will complain in the std-out logs, but you can turn that off and it works fine. They just don't guarantee that it will continue to work in future versions. I have also heard that it might screw up WebSphere's transaction management, but we don't have any container managed transactions so I don't know for sure.