ORA-00001: unique constraint (JON.RHQ_PACKAGE_VERSION_IDX) violated messages in the JON Server's log file

Issue

• Our rhq-server-log4j.log file shows the following exceptions:

ERROR [org.hibernate.util.JDBCExceptionReporter] ORA-00001: unique constraint (JON.RHQ_PACKAGE_VERSION_IDX) violated
ERROR [org.hibernate.event.def.AbstractFlushingEventListener] Could not synchronize database state with session
org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
...
Caused by: java.sql.BatchUpdateException: ORA-00001: unique constraint (JON.RHQ_PACKAGE_VERSION_IDX) violated
...
2012-03-24 15:31:10,038 WARN  [com.arjuna.ats.arjuna.logging.arjLoggerI18N] [com.arjuna.ats.arjuna.coordinator.TwoPhaseCoordinator_2] TwoPhaseCoordinator.beforeCompletion - failed for com.arjuna.ats.internal.jta.resources.arjunacore.SynchronizationImple@738945ce
javax.persistence.EntityExistsException: org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
...
Caused by: org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update
... 
Caused by: java.sql.BatchUpdateException: ORA-00001: unique constraint (JON.RHQ_PACKAGE_VERSION_IDX) violated
... 
2012-03-24 15:31:10,043 WARN  [org.rhq.enterprise.server.content.ContentManagerBean] There was probably a very big and ugly EJB/hibernate error just above this log message - you can normally ignore that. We detected that a package version was already created when we tried to do it also - we will ignore this and just use the new package version that was created in the other thread

How can we fix this?