Major Description
AMQ-850 introduced the ability to set the message prefetch size to 0.
This means that no messages are prefetched and every receive() call goes all the way to the broker to get the next message.
It was only a valid option for synchronous message receivers.
In CMS it does not appear to work. Instead, a client set to use this simply receives no messages, and the messages remain on the queue.
Without this patch, it is possible for a slow consumer to hide an important message from other consumers because it has prefetched it.