You are looking for the case where the ManagedConnection is used in a LocalTransaction, then put back into the pool, then retrieved but not enlisted in a transaction, correct ?
The comments in
org.jboss.resource.adapter.jms.JmsManagedConnection
provides some insight to this case inside an application server:
* <p>From the JMS tutorial:
* "When you create a session in an enterprise bean, the container ignores
* the arguments you specify, because it manages all transactional
* properties for enterprise beans."
*
* <p>And further:
* "You do not specify a message acknowledgment mode when you create a
* message-driven bean that uses container-managed transactions. The
* container handles acknowledgment automatically."
So the above case would be out-of-scope.