rfc1939.txt	POP3
rfc2821.txt	SMTP
rfc2822.txt	Internet Message Format
rfc977.txt	NNTP
rfc2045.txt	MIME 1
rfc2046.txt	MIME 2
rfc2047.txt	MIME 3
rfc2048.txt	MIME 4
rfc2049.txt	MIME 5
rfc2060.txt	IMAP4
rfc2015.txt	MIME Security with Pretty Good Privacy (PGP)
rfc2487.txt	SMTP Service Extension for Secure SMTP over TLS
