Voice messaging evolved as telephone answering service into a full send, receive, and forward messaging paradigm with unique message features, semantics and usage patterns. Voice messaging was introduced on special purpose computers that interface to a telephone switch and provide call answering and voice messaging services. Traditionally, messages sent from one voice messaging system to another were transported using analog networking protocols based on DTMF signaling and analog voice playback. As the demand for networking increases, there was a need for a standard high-quality digital protocol to connect these machines. VPIM has successfully demonstrated its usefulness as this new standard. VPIM is widely implemented and is seeing deployment in early adopter customer networks. This document clarifies ambiguities found in the earlier specification and is consistent with implementation practice. The profile is referred to as VPIM (Voice Profile for Internet Mail) in this document. This second revision of the version 2 of obsoletes RFC 2421 which less precisely describes version 2 of the profile.