https://issues.apache.org/jira/browse/AMQ-3805 - further resolution, dispatch and activate could clash over the audit resulting in skipped messages in the batch, the end result being our of order dispatch. Additional test and fix up of use of cache and sync between durable sub and prefetch sub
activemq/trunk/activemq-core/src/main/java/org/apache/activemq/broker/region/DurableTopicSubscription.java