Re: [apps-discuss] Mail client configuration via something, maybe WebFinger

"John Levine" <> Wed, 10 February 2016 18:24 UTC

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Subject: Re: [apps-discuss] Mail client configuration via something, maybe WebFinger
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>I am pleasantly surprised - you have an ISP that respects the RFC that states the user
>part *is* case sensitive. Most ignore that. Oh well.

No, that's not what the RFC says.  It says it's up to the mail system
to decide what the local part means.  It's perfectly valid for a mail
system to treat ASCII case variants of the local part of its mailboxes
as equivalent, and I have to say it's been a long time since I've seen
one that doesn't.

I wonder what system Doug is using that cares, and how old its code is.


PS: Where it gets a lot hairier is with optional characters like dots
in gmail names, optional suffixes like user+ext@domain or
user-ext@domain, and the whole world of EAI and UTF-8 where I am sure
there are all sorts of things that are obviously equivalent in some
languages and not in others.