Alexey Melnikov wrote:
RFC 821 allowed for space characters (0x20) in local part of
email addresses, but RFC 2821 and 2821bis don't allow for that
| <quoted-string> ::= """ <qtext> """
| <qtext> ::= "\" <x> | "\" <x> <qtext> | <q> | <q> <qtext>
[...]
| <q> ::= any one of the 128 ASCII characters except <CR>, <LF>, quote ("),|
or backslash (\)
That allowed NO-WS-CTL, SP, and NUL in a <quoted-string> *outside* of a
<quoted-pair>
Local-part = Dot-string / Quoted-string
; MAY be case-sensitive
Dot-string = Atom *("." Atom)
Atom = 1*atext
Quoted-string = DQUOTE *qcontent DQUOTE
where qcontent is defined in RFC 2822 as:
qtext = NO-WS-CTL / ; Non white space controls
%d33 / ; The rest of the US-ASCII
%d35-91 / ; characters not including "\"
%d93-126 ; or the quote character
qcontent = qtext / quoted-pair
NO-WS-CTL = %d1-8 / ; US-ASCII control characters
%d11 / ; that do not include the
%d12 / ; carriage return, line feed,
%d14-31 / ; and white space characters
%d127
Was this change between RFC 821 and RFC 2821 intentional? Prohibition of
spaces in quoted parts breaks gatewaying to/from X.400 (MIXER, RFC 2156).
Regards,
Alexey