Notes:
It is not clear what the message-id of a confirmation request should be. The example XML shows, in the ice-code tag, a message-id attribute that looks like a request id from the syndicator. That's confusing, because the syndicator has sent no request to the subscriber, has it? Here's what I think happens:
1) Subscriber sends request to syndicator
2) Syndicator sends reply with confirmation="true"
3) Subscriber sends request with ice-code 201 (confirmation).
Where did the XML example in item 3 get the message-id of "REQ-...BradsGadgets-2397" from?
Streamed different: payloads, ice-items, ice-item-refs, catalogs, etc.