Well, that one was easy, thanks to this post: https://www.manning-sandbox.com/message.jspa?messageID=56075 I just added the configuration to my persistence.xml file: <persistence> | <persistence-unit name="crunch"> | <jta-data-source>java:/CrunchDS</jta-data-source> | <properties> | <property name="hibernate.hbm2ddl.auto" value="create-drop"/> | <property name="hibernate.dialect" value="org.hibernate.dialect.MySQLDialect"/> | <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/> | <property name="hibernate.connection.url" value="jdbc:mysql://localhost/crunch"/> | <property name="hibernate.connection.username" value="blah"/> | </properties> | </persistence-unit> | </persistence> The EAR is now deployed, albeit with a huge number of exceptions. I think the problem now is that the location of the mysql-connector jar file (mysql-connector-java-5.0.5-bin.jar) needs to be changed. I used to put it in server/default/lib but I get these errors on the deploy: | 11:38:11,319 INFO [ConnectionFactoryBindingService] Bound ConnectionManager 'jboss.jca:service=DataSourceBinding,name=CrunchDS' to JNDI name 'java:CrunchDS' | 11:38:11,339 INFO [EARDeployer] Init J2EE application: file:/home/mjhammel/src/cei/jboss-4.2.2.GA-cei/server/default/deploy/Crunch.ear | 11:38:11,422 INFO [JmxKernelAbstraction] creating wrapper delegate for: org.jboss.ejb3.entity.PersistenceUnitDeployment | 11:38:11,423 INFO [JmxKernelAbstraction] installing MBean: persistence.units:ear=Crunch.ear,unitName=crunch with dependencies: | 11:38:11,423 INFO [JmxKernelAbstraction] jboss.jca:name=CrunchDS,service=DataSourceBinding | 11:38:11,425 INFO [PersistenceUnitDeployment] Starting persistence unit persistence.units:ear=Crunch.ear,unitName=crunch | 11:38:11,436 INFO [Configuration] Reading mappings from resource : META-INF/orm.xml | 11:38:11,437 INFO [Ejb3Configuration] [PersistenceUnit: crunch] no META-INF/orm.xml found | 11:38:11,443 INFO [ConnectionProviderFactory] Initializing connection provider: org.hibernate.ejb.connection.InjectedDataSourceConnectionProvider | 11:38:11,444 INFO [InjectedDataSourceConnectionProvider] Using provided datasource | 11:38:11,447 WARN [JBossManagedConnectionPool] Throwable while attempting to get a new connection: null | org.jboss.resource.JBossResourceException: Could not create connection; - nested throwable: (org.jboss.resource.JBossResourceException: Failed to register driver for: com.mysql.jdbc.Driver; - nested throwable: (java.lang.ClassNotFoundException: No ClassLoaders found for: com.mysql.jdbc.Driver)) The HSQL jar files all seem to be in server/default/lib, so my gut feeling is that the mysql-connector jar file is also supposed to go here. If so, then this problem is not about the connector. More googling.... View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4115768#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...