I just use the a spring JtaTransactionManager which acts as a TM wrapper that looks up JBoss UserTx and TM in jndi, and allow consistent syntax when switching to a spring-specific TM. I dont know the spring code base by heart but it has to properly call commit on the jboss resources as I do have consitent distributed tx behaviour for my commits and rollbacks between JBM and Hibernate. Anyway, I did setup a one class test bootstraped as a sar and using a thread pool executor for the multithreading and I can see the same ever groging ServerConsumerEndpoint count with JHat (with both TransactionManager and UserTransaction). Would you have a few minutes to look into it ? I can send it to you if you're interested. Thanks, Best regards Olivier View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4019473#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...