What Meng said

In rereading the Jabber logs and reading the recent threads on 
SUBMITTER, I'd like to point everyone to a simple sentence Meng wrote 
in the Jabber session:  
http://www.xmpp.org/ietf-logs/marid(_at_)ietf(_dot_)xmpp(_dot_)org/2004-08-04.html
>  [11:05:42] <mengwong> if submitter is not present, we fall back to 
> mail-from. people are missing this.
In defense of "people", I reread marid-submitter and marid-core this 
morning and could not find the place where this was stated.  However, 
this statement is significant.  I'm not saying it is a good or bad 
idea, but it profoundly changes how SUBMITTER is used, the nexus of 
SUBMITTER and PRA, and even the semantics of the RR version identifier.
-andy