This is NOT the same thing as setting DUPS_OK_ACKNOWLEDGE on the gateway's jms-message-filter. This is about the QoS of the whole service, not just the inbound JMS listener. To get the same behavior as QOS_DUPLICATES_OK in the JBM Bridge, basically, the ESB needs to set the ack mode to CLIENT_ACKNOWLEDGE on the source, then wait until the service has finished processing the message (which may or may not involve the message moving on to other queues), then finally acknowledge the message. This shouldn't be that hard to implement.
One way I propose this might be configured, is to have this behavior occur automatically when the jms-message-filter is configured with CLIENT_ACKNOWLEDGE. This could be decided to mean that it'll get acknowledge when the service completes, but then a service developer could optionally acknowledge it themselves in an action if they wanted too. (speaking of which, that'd make a nice built-in action to provide with the ESB).
See the following source code file to gain incite into this:
And finally the forum reference below should be highly relevant.