mattupstate/flask-mail — pull request #39 by mrluanma (2013-07-09 01:24:57+00:00)
Title: Sanitized sendmail's from_addr parameter.

or Mail.send_message with MAIL_DEFAULT_SENDER as ('XXXX', 'no-reply@xxx.com') will raise exception: SMTPSenderRefused(501, 'mail from address must be same as authorization user', ('XXXX', 'no-reply@xxx.com'))