SCHEME for FULL-SPEC RETURN PATH

[Hal]

> From: Matthew J Ghio <mg5n+ at andrew.cmu.edu>
> 
> > From: "Jon 'Iain' Boone" <boone at psc.edu>
> > 
> >  To: anon3+"(anon2+"(anon1+"(boone at psc.edu)Ka"@a.edu)Kb"@b.com)Kc"@c.org
> >  From: wcs at anchor.ho.att.com
> >  Message-Id: <99234.AA23492383 at anchor.ho.att.com>
> >
> >  C.ORG:
> >
> >  To: anon2+"(anon1+"(boone at psc.edu)Ka"@a.edu)Kb"@b.com
> >  From: wcs at anchor.ho.att.com
> >  Message-Id: <2342349324.AA2343242 at c.org>
> ...
> 
> Well, I guess great minds think alike.  I'm already working on this. 
> I've been hacking on in my spare time for about a month now.  My program
> is about 75-80% done.  Here's how it will work:
> 
> You send mail to remail+getid at x.edu.

Is this some kind of RFC822 hack?  It doesn't work on my system.  Mail to
hfinney+xyz at shell.portal.com bounces.  Are you assuming some special
mail address processing has been installed by the administrators of the
machines to handle this "+" hack, or is my machine broken in not respecting
it?

Hal