On Fri, May 13, 2005 at 03:51:03AM -0400,
Valdis(_dot_)Kletnieks(_at_)vt(_dot_)edu
<Valdis(_dot_)Kletnieks(_at_)vt(_dot_)edu> wrote
a message of 28 lines which said:
John Klensin posted here back in 2002 that those references to 2.4.1
were incorrect and should be to 6.3 instead.
Not all of them.
4.1.1.1 Extended HELLO (EHLO) or HELLO (HELO)
...
Although EHLO keywords may be specified in upper, lower, or mixed
case, they MUST always be recognized and processed in a case-
insensitive manner. This is simply an extension of practices
specified in RFC 821 and section 2.4.1.
Here, 6.3 never talks about case. It is certainly 2.4:
Verbs and argument values (e.g., "TO:" or "to:" in the RCPT command
and extension name keywords) are not case sensitive,