Persistence.beginTransaction();
        Client client = new Client("deadlock test", new HashSet());
        Campaign campaign = new Campaign("deadlock test", client);
        Persistence.save(client);
        Persistence.commitTransaction();
        Persistence.closeSession();

        // Normally there is only ever one session per thread.  But in this test case
        // we require two sessions.  So we use the testing-only method to get them.
        Session session1 = Persistence.testingOnlyGetJdbcSessionFactory().openSession();
        Session session2 = Persistence.testingOnlyGetJdbcSessionFactory().openSession();
        Transaction tx1 = session1.beginTransaction();
        Transaction tx2 = session2.beginTransaction();

        Client client1 = (Client)session1.createQuery("from Client client where client.name = ?")
                .setParameter(0, "deadlock test", Hibernate.STRING)
                .uniqueResult();
        Campaign campaign1 = (Campaign)client1.getCampaigns().iterator().next();

        Client client2 = (Client)session2.createQuery("from Client client where client.name = ?")
                .setParameter(0, "deadlock test", Hibernate.STRING)
                .uniqueResult();
        Campaign campaign2 = (Campaign)client2.getCampaigns().iterator().next();

        // now try modifying the clients and campaigns in an interleaved order
        campaign2.setName("deadlock test 2");
        client1.setName("deadlock test 1");

        session1.flush();
        session2.flush();

        client2.setName("deadlock test 2");
        campaign1.setName("deadlock test 1");

        session1.flush();
        session2.flush();

        tx1.commit();
        tx2.commit();
        session1.close();
        session2.close();

    [junit] Testcase: testDeadlock(com.nimblefish.core.test.persist.PersistenceManagerTest):    Caused an ERROR
    [junit] Could not execute JDBC batch update
    [junit] net.sf.hibernate.JDBCException: Could not execute JDBC batch update
    [junit]     at net.sf.hibernate.impl.BatcherImpl.executeBatch(BatcherImpl.java:125)
    [junit]     at net.sf.hibernate.impl.SessionImpl.executeAll(SessionImpl.java:2311)
    [junit]     at net.sf.hibernate.impl.SessionImpl.execute(SessionImpl.java:2262)
    [junit]     at net.sf.hibernate.impl.SessionImpl.flush(SessionImpl.java:2187)
    [junit]     at com.nimblefish.core.test.persist.PersistenceManagerTest.testDeadlock(PersistenceManagerTest.java:672)
    [junit]     at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    [junit]     at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    [junit]     at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    [junit]     at junit.extensions.TestDecorator.basicRun(TestDecorator.java:22)
    [junit]     at junit.extensions.TestSetup$1.protect(TestSetup.java:19)
    [junit]     at junit.extensions.TestSetup.run(TestSetup.java:23)
    [junit] Caused by: java.sql.BatchUpdateException: General error,  message from server: "Lock wait timeout exceeded; Try restarting transaction"
    [junit]     at com.mysql.jdbc.PreparedStatement.executeBatch(PreparedStatement.java:1469)
    [junit]     at net.sf.hibernate.impl.BatchingBatcher.doExecuteBatch(BatchingBatcher.java:54)
    [junit]     at net.sf.hibernate.impl.BatcherImpl.executeBatch(BatcherImpl.java:118)
    [junit]     ... 24 more