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suspect error in SMTP ta handling of empty from envelope address

Just a heads up:

I believe there is an error in the way the SMTP transport agent handles
messages that originate as errors -- that is, messages which arrived via SMTP
with an empty reverse path -- for example:

	HELO foo.some.site
	RCPT TO:<luser@some.other.site>
	Subject: non delivery notice
	From: mailer-daemon@some.site
	To: luser@some.other.site

This shows up in the file passed to the router as:

	rcvdfrom foo.some.site ([a.b.c.d])
	channel error
	to <luser@some.other.site>

and it makes its way on to the scheduler, and finally to the transport agent
(in this example, say it's the SMTP ta).

The SMTP ta sends

	HELO me.my.site
	MAIL FROM:<mailer-daemon@some.site>
	RCPT TO:<luser@some.other.site>

because the scheduler said "s error  foo.some.site mailer-daemon@some.site" in
the control file, and the SMTP ta just picks up the originating address to use
in the MAIL FROM: command.   WRONG!  It needs to notice that the message
originated from the error channel, and therefore it should use an appropriate
MAIL FROM: address (i.e., <>).

I am watching a rather large (and growing) message transiting (fortunately,
slowly) back and forth via my gateway, while I read the SMTP ta code.