Re: What characters can be in an email address?

Timothy J Luoma <luomat+Lists/procmail(_at_)luomat(_dot_)peak(_dot_)org> writes:
> Not sure if there's an RFC on this (Era will know I'm sure ;-) but I was  
> wondering what non a-z 0-9 characters are considered "legal" as part of an  
> email address.... or maybe what aren't?
According to rfc822, any ascii character (codes 0 to 127) can appear in
the local part of an e-mail address as long as they're quoted
properly.  Thus, the following is syntacically legal:

        "(_at_)!,\"\\'<>()%:;"@gac.edu

The local part of that address is, with quoting stripped:

        (_at_)!,"\'<>()%:;


If the local part of the address consists only of alphanumerics and the
following:

                ! # $ % & ' * + - / = ? ^ _ ` { | } ~

then it doesn't need to be quoted.

It is now strongly recommended that NULs (ascii code 0) not be used,
even inside double-quotes, and that CR and LF not be used by
themselves, even escaped inside double-quotes.  Such usage is
considered obsolete, and though parser are _supposed_ to continue to
accept such syntax, many don't.


Philip Guenther