http://www.rfc-editor.org/rfc/rfc5550.txt
RFC 5550: The Internet Email to Support Diverse Service Environments (Lemonade) Profile, D. Cridland, A. Melnikov, S. Maes2009-08-01T23:00:00-00:00The Lemonade Profile relies upon several extensions to IMAP, Sieve, and Mail Submission protocols. The document also defines a new IMAP extension and registers several new IMAP keywords. [STANDARDS-TRACK]