User development, A new message was posted in the thread "jbpm 4.3 - org.hibernate.exception.ConstraintViolationException: Could not execute JDBC batch update": http://community.jboss.org/message/522469#522469 Author : Zengping Tian Profile : http://community.jboss.org/people/zptian Message: -------------------------------------------------------------- Thanks for sharing Martin   Interesting to know that you have done the test to add continue="async" on the Start activity. We did the similar test and found the same issue. Hope someone from the JBPM team could explain whether it's a known problem which will be fixed in the future release.   In our case we use DB2 9.1.7 and running JBPM as a standalone server(wrap up JBPM in a java process ) with out of box job executors.The issue we experienced frequently is db2 SQL exception of deadlock(SQL Error code -911) on JBPM4_EXECUTION, and sometimes on JBPM4_JOB as well. The different errors we saw could be due to the differences between Oracle and DB2 on the default constrains of the tables and the isolation levels. The cause could be the same underlyer issue or issues. As you pointed out, the ID generator could be a point of issue. We also doubt about the way JBPM handling the subprocess activity as while as it seems running fine if we strip off the subprocess.   We have pushed our QA for two weeks because of this issue. We'll give a shot to the id generator to see if we can do anything. Will keep you posted.   Thanks ZT -------------------------------------------------------------- To reply to this message visit the message page: http://community.jboss.org/message/522469#522469