David:
The first paragraph in section 3.1.6.4 in the version 1.091 draft now reads:
"If the TimeToLive element is present, it MUST be used to indicate the time,
expressed in UTC, by which a message should be delivered to the To Party. It
must conform to an XML Schema dateTime."
I think the phrase "To Party" should be replaced with "To Party MSH". The To
Party MSH will check the incoming message to determine if its TimeToLive has
expired. It may have to make a persistent copy of the message before
attempting to deliver it to the To Party. A crash may happen after the
message has been persisted but prior to its being delivered to the To Party.
Therefore, it is entirely possible that the To Party only receives the
message after TimeToLive has passed.
Regards,
-Arvola