Mapping Between the Multimedia Messaging Service (MMS) and Internet Mail
RFC 4356

Received changes through RFC Editor sync (changed abstract to 'The cellular telephone industry has defined a service known as the Multimedia Messaging Service (MMS). This service uses formats and protocols that are similar to, but differ in key ways from, those used in Internet mail.

One important difference between MMS and Internet Mail is that MMS uses headers that start with "X-Mms-" to carry a variety of user agent- and server-related information elements.

This document specifies how to exchange messages between these two services, including mapping information elements as used in MMS X-Mms-* headers as well as delivery and disposition reports, to and from that used in SMTP and Internet message headers. [STANDARDS-TRACK]')