Name,Status,Multicast-Mail-Specific References,Non-Multicast-Specific References,Note
SIZE,Required,,[RFC1870],
8BITMIME,Required,,[RFC6152],
DSN,Required,,[RFC3461],
MT-PRIORITY,Required,,[RFC6710],
DELIVERBY,Required,,[RFC2852],
BINARYMIME,Required,,[RFC3030],
CHUNKING,Special,,[RFC3030],"SMTP CHUNKING MUST be supported on the receiving SMTP side of
        an SMTP-to-MULE gateway and MAY be used on the sending side of a
        MULE-to-SMTP gateway. A MULE relay doesn't need to do anything
        special for this extension."
ENHANCEDSTATUSCODES,Special,,[RFC2034],"The ENHANCEDSTATUSCODES extension is supported by including
        relevant status codes in DSN [RFC3461] reports."
RRVS,Supported,,[RFC7293],
SUBMITTER,Supported,,[RFC4405],"Deprecated by [Moving RFC 4405, RFC 4406, RFC 4407 (Sender-ID) to Historic]."
PIPELINING,N/A,,[RFC2920],
STARTTLS,N/A,,[RFC3207],
AUTH,Special,,[RFC4954],"The AUTH parameter to the MAIL FROM command is ""Supported"",
        but the rest of the AUTH extension is not applicable to MULE."
BURL,N/A,,[RFC4468],
NO-SOLICITING,N/A,,[RFC3865],
CHECKPOINT,Disallowed,,[RFC1845],
CONNEG,Disallowed,,[RFC4141],