Default validation fails with umlaut in name part

[JayQ1982]

Validation of "testümläü[email protected]" fails when i use default $patternselect value "php".

This could be fixed in validateAddress()-method by changing

return (bool) filter_var($address, FILTER_VALIDATE_EMAIL);
to
return (bool) filter_var($address, FILTER_VALIDATE_EMAIL, FILTER_FLAG_EMAIL_UNICODE);

[Synchro]

That's because Unicode in the local part is not valid unless you support RFC6531, which PHPMailer does not (yet), and it involves a lot more than changing address validation; it's also dependent on the server you connect to supporting it.