A-MQ queues with messages not visible via JMX until additional message added

Issue

• We have noticed that when AMQ is restarted, queues are not visible via JMX until a messages is placed on them. For queues with no messages this behaviour is fine (and expected). However, this also occurs for queues with messages on them. This will be a problem for support as it makes it difficult to recover messages on DLQ's in particular if AMQ goes down."