And if I remove the ProcessInstanceLog etc entities from persistence.xml, I get the following exception :
org.hibernate.ejb.connection.InjectedDataSourceConnectionProvider
00:37:24,288 ERROR [org.jboss.msc.service.fail] (MSC service thread 1-2) MSC000001: Failed to start service jboss.persistenceunit."jbpmDemo.war#org.jbpm.persistence.jpa": org.jboss.msc.service.StartException in service jboss.persistenceunit."jbpmDemo.war#org.jbpm.persistence.jpa": Failed to start service
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1767) [jboss-msc-1.0.2.GA-redhat-1.jar:1.0.2.GA-redhat-1]
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) [rt.jar:1.6.0_31]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) [rt.jar:1.6.0_31]
at java.lang.Thread.run(Thread.java:662) [rt.jar:1.6.0_31]
Caused by: javax.persistence.PersistenceException: [PersistenceUnit: org.jbpm.persistence.jpa] Unable to build EntityManagerFactory
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:915)
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:890)
at org.hibernate.ejb.HibernatePersistence.createContainerEntityManagerFactory(HibernatePersistence.java:74)
at org.jboss.as.jpa.service.PersistenceUnitServiceImpl.createContainerEntityManagerFactory(PersistenceUnitServiceImpl.java:162)
at org.jboss.as.jpa.service.PersistenceUnitServiceImpl.start(PersistenceUnitServiceImpl.java:85)
at org.jboss.msc.service.ServiceControllerImpl$StartTask.startService(ServiceControllerImpl.java:1811) [jboss-msc-1.0.2.GA-redhat-1.jar:1.0.2.GA-redhat-1]
at org.jboss.msc.service.ServiceControllerImpl$StartTask.run(ServiceControllerImpl.java:1746) [jboss-msc-1.0.2.GA-redhat-1.jar:1.0.2.GA-redhat-1]
... 3 more
Caused by: org.hibernate.MappingException: Could not determine type for: java.util.Set, at table: ProcessInstanceInfo, for columns: [org.hibernate.mapping.Column(eventTypes)]
at org.hibernate.mapping.SimpleValue.getType(SimpleValue.java:305)
at org.hibernate.mapping.SimpleValue.isValid(SimpleValue.java:289)
at org.hibernate.mapping.Property.isValid(Property.java:238)
at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:468)
at org.hibernate.mapping.RootClass.validate(RootClass.java:270)
at org.hibernate.cfg.Configuration.validate(Configuration.java:1294)
at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1736)
at org.hibernate.ejb.EntityManagerFactoryImpl.<init>(EntityManagerFactoryImpl.java:93)
at org.hibernate.ejb.Ejb3Configuration.buildEntityManagerFactory(Ejb3Configuration.java:905)
... 9 more