Currently, i had trying out Sun Studio 5 which used Sun ONE Application Server. Database is MySQL server. I had config the JDBC in Sun ONE Application Server to link to MySQl server (including Connection Pools, JDBC Resources and Persisent Manager). I created a simple container managed EJB. I had to specific the CMR resouce in the web module. I point CMR resouce to Persistence manager of MySQL. It did not work after i deployed EAR. I point CMR resouce to JDBC Resources. It did not work too. However, I created a simple bean managed EJB. It work. Can anybody help me on this.