In the queue case, when a consumer was closed it was not properly re-delivering messages to other available consumers. This was causing message to look like they got dropped. - When we shut a queue sub down we now get it's pending+dispatched list and re-dispatch that to the other available subscriptions.
activemq/trunk/activemq-core/src/main/java/org/apache/activemq/broker/region/AbstractSubscription.java