strange timing problem in /usr/ucb/Mail

[King Ables]

We noticed a strange timing problem in /usr/ucb/Mail today
that we've been seeing for some time (so I suspect it exists
in MANY versions).  We are currently running SunOS 3.5 on
the machine where the problem occurs, but have observed *at
least* as far back as 3.0.  I suspect it exists from the original
Berkeley code.

The problem occurs when replying to a message which many
recipients and you ^D at the end of the message and the CC:
line is shown to you (you have askcc set in your .mailrc).
If the Cc: line has several addresses on it so that it wraps
to a 2nd line AND if you hit ^D and <RETURN> (the <return> in
response to the Cc: line prompt) VERY QUICKLY, there seems
to be a timing problem where the 2nd line's worth of text (the
part that was wrapped) isn't gathered up and processed so you
wind up with a partial CC: line going out.  This has the effect
of possibly leaving some people off the Cc: line and usually
cutting some address in half so that it no longer is a valid
address (half a hostname or some such).

Has anyone noticed this before and has anyone ever done anything
about it?  I don't want to go figuring it out for myself is someone
already has fixed it.

Thanks for any info.

-king
ARPA: ables at mcc.com
UUCP: {gatech,nbires,seismo,ucb-vax}!cs.utexas.edu!pp!ables