NEW ISSUE: MessageNumber on AckReq

[Doug Davis <dug@us.ibm.com>]

Title: MessageNumber on AckReq

Description/Justifcation:

The spec [1] says:
This OPTIONAL element, if present, MUST
contain an xs:unsignedLong representing the highest <wsrm:MessageNumber>
sent by the RM Source within the Sequence. If present, it MAY be treated
as a hint to the RM Destination as an optimization to the process of preparing
to transmit a <wsrm:SequenceAcknowledgement>.

This additional element seems to provide
no real value.  I'd like to understand the motivation behind it.  What
kind of optimizations are we talking about?  If the optimization is
related to "when" to send back the Ack then we have a problem
since the spec says that the RMD MUST respond with a SeqAck - and while
not explicitly stated I think its implied that it should return it as soon
as possible.  So, what additional value is this providing?  I
fear that, like LastMessage, people may read more into this than intended
and make assumption about its purpose that are not true. If it provides
no additional value, that we can specify in the spec, we should remove
it.

Target: core

Proposal:  Remove MessageNumber
from AckRequested element

[1] http://www.oasis-open.org/apps/org/workgroup/ws-rx/download.php/15001/wsrm-1.1-spec-wd-05.pdf