-<cipher-suite-spec> should be a cipher specification for OpenSSL,
-e.g., HIGH:MEDIUM:+SSLv2.
+<cipher-suite-spec> should be a cipher specification for
+the TLS library in use (OpenSSL, GnuTLS, or Mozilla NSS).
+Example:
+.RS
+.RS
+.TP
+.I OpenSSL:
+TLS_CIPHER_SUITE HIGH:MEDIUM:+SSLv2
+.TP
+.I GnuTLS:
+TLS_CIPHER_SUITE SECURE256:!AES-128-CBC
+.RE
+
+To check what ciphers a given spec selects in OpenSSL, use:
+
+.nf
+ openssl ciphers \-v <cipher-suite-spec>
+.fi
+
+With GnuTLS the available specs can be found in the manual page of
+.BR gnutls\-cli (1)
+(see the description of the
+option
+.BR \-\-priority ).
+
+In older versions of GnuTLS, where gnutls\-cli does not support the option
+\-\-priority, you can obtain the \(em more limited \(em list of ciphers by calling:
+
+.nf
+ gnutls\-cli \-l
+.fi
+
+When using Mozilla NSS, the OpenSSL cipher suite specifications are used and
+translated into the format used internally by Mozilla NSS. There isn't an easy
+way to list the cipher suites from the command line. The authoritative list
+is in the source code for Mozilla NSS in the file sslinfo.c in the structure
+.nf
+ static const SSLCipherSuiteInfo suiteInfo[]
+.fi
+.RE