3 rfc2015.txt MIME Security with Pretty Good Privacy (PGP)
10 rfc2183.txt The Content-Disposition Header Field
11 rfc2342.txt IMAP4 Namespace
12 rfc2359.txt IMAP4 UIDPLUS extension
13 rfc2487.txt SMTP Service Extension for Secure SMTP over TLS
15 rfc2822.txt Internet Message Format
16 rfc2980.txt Common NNTP Extensions