Re: Recap on mail message compatibility with RFC822 [and it's successor]

[Greg Hudson]

> Neither of these are problems at the moment because nobody is doing
> this stuff.  But if, for example, Microsoft decided to being every
> mail header field name with a NUL it would be legal while breaking
> lots of things.

It would be legal according to RFC 822, but not according to RFC 2822.
(RFC 2822 defines NUL and bare CR and LF to be obsolete, and requires
that receivers must accept them but senders may not send them.)