"Address or Header Error-1"

Without provocation exmh started complaining like so:

    send: please re-edit draft to remove the ``X-Mailer'' header!

Whenever I press the "Send" button or "More... Whom".  It looks like
exmh is prepending an "X-Mailer" to the top of the mail draft,
indeed this is it:

    X-Mailer: exmh version 2.7.0 06/18/2004 with nmh-1.0.4

Everything worked fine around noon.  Then 2.5 hours later it
broke.  Honestly, I didn't change a thing.  Nothing bad shows up
in /var/log/mail/* nor /var/log/syslog.

Does anyone have a clue as to how to fix this?  Help?  Pretty please?

Thanks....

P.S.:	I composed this message in exmh, but had to edit the
	draft and send it with comp from command-line.

--
Kevin