DR051 and DR006: Identification of message

DR051:
"A message must have a globally unique identifier."

DR006:
"
Support uniquely identifying messages as entities, so that correlating
related message (such as requests and responses) is possible over any
transport. 
Issue (i.006.01):

The use of the word "entity" is confusing with the XML use of the term.
"

I think that these two requirements are similar enough that the resulting
requirement will probably encompass them both.

It might be hard to enforce the use of a globally unique identifier per
message, so I suggest the following:

"An XP message must be able to support a globally unique identifier to
identify itself."

(not to be confused with an identifier for an XP sender or XP receiver)

Comments?

Alex