I googled and found this site where you can dowload all the varia jars, including derby-plugin-4.0.4 http://rpm.pbone.net/index.php3/stat/4/idpl/3691384/com/jboss4-varia-4.0.... hope it helps. Since it is added to the server/xxx/ib the Derby NPE has gone but another problem shows up: 13:43:31,828 INFO [WrapperDataSourceService] Bound ConnectionManager 'jboss.jca :service=DataSourceBinding,name=DerbyDS' to JNDI name 'java:DerbyDS' 13:43:32,000 WARN [ServiceController] Problem starting service jboss.mq:service =PersistenceManager javax.management.AttributeNotFoundException: not found: BindName at org.jboss.mx.server.AbstractMBeanInvoker.getAttribute(AbstractMBeanIn voker.java:335) If I remove the hsqldb-ds.xml file this error goes but anohter unfriendly message shows up: 13:47:12,656 INFO [TomcatDeployer] deploy, ctxPath=/jmx-console, warUrl=.../dep loy/jmx-console.war/ 13:47:12,859 ERROR [URLDeploymentScanner] Incomplete Deployment listing: --- MBeans waiting for other MBeans --- ObjectName: jboss.ejb:service=EJBTimerService,persistencePolicy=database State: CONFIGURED I Depend On: jboss.jca:service=DataSourceBinding,name=DefaultDS ObjectName: jboss.mq:service=StateManager State: CONFIGURED I Depend On: jboss.jca:service=DataSourceBinding,name=DefaultDS Depends On Me: jboss.mq:service=DestinationManager This means that it must be more config to use Derby instead of HSQLDB View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3997898#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...