Markus Schönhaber wrote: > 07.04.26, 18:29 +0100, Joe: > > > I'm fairly sure that neither the SMTP protocol nor exim in particular > > distinguish cases in email addresses. I have a feeling I found this for > > sure with exim4, but I've run it for so many years I can no longer > > remember the details. > > I don't know anything about exim, but the SMTP protocol defines the > local-part of an email address to be case-sensitive: > > | The local-part of a mailbox MUST BE treated as case sensitive. > | Therefore, SMTP implementations MUST take care to preserve the case > | of mailbox local-parts. In particular, for some hosts, the user > | "smith" is different from the user "Smith". However, exploiting the > | case sensitivity of mailbox local-parts impedes interoperability and > | is discouraged. Mailbox domains follow normal DNS rules and are > | hence not case sensitive. > > https://www.rfc-editor.org/rfc/rfc5321.html#section-2.4
[email protected] is different from [email protected], but [email protected] is the same as [email protected]. -dsr-
