multipart/alternative 'IANA,RFC2045,RFC2046
multipart/appledouble 'IANA,[Faltstrom]
multipart/byteranges 'IANA,RFC2616
multipart/digest 'IANA,RFC2045,RFC2046
multipart/encrypted 'IANA,RFC1847
multipart/example 'IANA,RFC4735
multipart/form-data 'IANA,RFC2388
multipart/header-set 'IANA,[Crocker]
multipart/mixed 'IANA,RFC2045,RFC2046
multipart/parallel 'IANA,RFC2045,RFC2046
multipart/related 'IANA,RFC2387
multipart/report 'IANA,RFC3462
multipart/signed 'IANA,RFC1847
multipart/voice-message 'IANA,RFC2421,RFC2423