FYI.
I was in Gmail team and wrote the email address validation code which we are
currently using.
Gmail's validation rules are:
- require "@"
- local-part should be
- quoted-string without CFWS and FWS, or
- 1*(atext / ".") This means dot-atom-text without "." restriction.
This looseness was introduced for Japanese cell phone addresses.
- domain-part should be [a-zA-Z0-9]+(\.[a-zA-Z0-9]+)+
It requires at least 1 dot. The last non-dot sequence should have at
least 2 characters.
I have never heard requests to support for non-ASCII characters other than
IDN.
--
TAMURA Kent
Software Engineer, Google
