An updated internet-draft is available from the IETF.
Abstract: «The requirement for the presence of a syntactically-valid message header From field in the Internet Message Format presents a problem in some circumstances. This memo (if approved) amends the Internet Message Format specifications to make that field optional. Discussion of the subject matter covered in this memo has taken place on the ietf-822 mailing list, and that would be a suitable place for discussion of this document.»