[rules-users] How has JPAKnowledgeService changed from 5.1.0.M2 to 5.1.0.FINAL?

We're using stateful knowledge sessions created by JPAKnowledgeService.newStatefulKnowledgeSession to execute Drools Flow rule flows, mainly consisting of a sequence of work items. With 5.1.0.M2, everything works as expected. However, with 5.1.0 (final release), when the rule flow starts the following is output by log4j: 2010-08-20 16:59:41,264 WARN [org.drools.persistence.session.JtaTransactionManager] - Participating in existing JTA transaction, but no JTA TransactionManager or TransactionSychronizationRegistry available: Then the rule stops before completion with: 2010-08-20 17:01:12,500 WARN [org.hibernate.util.JDBCExceptionReporter] - SQL Error: 0, SQLState: null 2010-08-20 17:01:12,500 ERROR [org.hibernate.util.JDBCExceptionReporter] - error enlisting a JdbcConnectionHandle of a JdbcPooledConnection from datasource jdbc/BitronixJTADataSource in state ACCESSIBLE wrapping oracle.jdbc.driver.T4CXAConnection@1c47258 on oracle.jdbc.driver.LogicalConnection@2f1a5f The configuration is pretty standard (Bitronix transaction manager, Oracle 11g database). We'd like to use the final release of 5.1.0 rather than a milestone, but this problem is holding us back. Does anyone have any idea what the problem is? What's changed with Drools Flow state persistence between 5.1.0.M2 and 5.1.0? Any help would be gratefully received. Thank you. Alan