In a Message of  andrew clarke (3:635/727.4) Wrote:

 ac> The purpose of MSGID/REPLY is to aid duplicate message detection and
 ac> provide a method to base reply linking upon.  MSGID/REPLY lines should
 ac> not be used to obtain addressing information, this was not their
 ac> purpose.

If I can't get the originating address from " # Origin: ", "
* Origin: "
and that I can't get it from the binary message header (which usually only
contains net/node information) then I try to get it from "^aTOMSG: ",
"^aINTL (first part)", "^aFMPT ", if it's a netmail
message, but else, I
check at the "a^MSGID: " and if it doesn't have one, then I got no choice,
it's only the 2d address I got (net/node).
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