MAIL WARS Part VI: The Revenge of X.400

There is an X.400 -> MIME gateway that sends headers like:
        Mime-Version: 1.0
        Content-Type:
Yes, a Content-Type header with no information.  That tripped up c-client
(actually, I had the error checking, but the error case fell into the wrong
code).

I wonder who else will stumble up against this.