swiftmailer/swiftmailer — pull request #436 by vlatosev (2014-02-28 01:06:34+00:00)
Title: XOauth2 authentification for SMTP servers.

Perhaps it may be useful to add OAuth2.0 authentication that is implemented on Gmail and MS Outlook servers (I don't know for any other).
Here is infos:
http://msdn.microsoft.com/en-us/library/live/dn440163.aspx
https://developers.google.com/gmail/xoauth2_protocol