Jan P. Kessler:
> Hi,
>
> sorry, I know this is not directly related to postfix but I know that
> there are several very experienced people reading this list. My question
> is how you (the people that use and administer mailservers) handle the
> localpart case sensivity according to rfc5321:
>
> "The local-part of a mailbox MUST BE treated as case sensitive."
This is about preserving addresses case. That is important for
transit email, but it has nothing to do with access policy.
When Postfix is final destination, whether case is preserved depends
the message store. For example, delivery to UNIX system accounts
is case-insensitive with respect to the envelope recipient.
For rate limits and other policies it makes a lot of sense to keep
them case-insensitive.
Wietse
