Jay R. Ashworth wrote:
I misunderstood you to be talking about RHSs. LHSs *must* be treated as case-sensitive, regardless how many providers don't actually do it that way.
Without any other data, they must. That's why i'm proposing it as a list of providers, rather than on a global basis. If we positively know that they're internaly case-insensitive, and treating them as such will make life easier for our users. Why not do it?
RFC 2822 and 1136, I think.
My think is that they're 821 and 2821 :-)
The case-insensitivity of RHSs devolves from the DNS RFCs, so neither 2821 nor 2822. RFC 1035, actually, s 2.3.3.
RFC 1035 is from November 1987.
RFC 821 (August 1982), section 2; Commands and replies are not case sensitive. That is, a command or reply word may be upper case, lower case, or any mixture of upper and lower case. Note that this is not true of mailbox user names. For some hosts the user name is case sensitive, and SMTP implementations must take case to preserve the case of user names as they appear in mailbox arguments. Host names are not case sensitive.