--- * RFC 2388 says that non-ASCII field names are encoded according
--- to the method in RFC 2047
--- <http://www.faqs.org/rfcs/rfc2047.html>, but they won't be
--- decoded.
+-- * RFC 2388 (<http://tools.ietf.org/html/rfc2388#section-3>) says
+-- that non-ASCII field names are encoded according to the method in
+-- RFC 2047 (<http://tools.ietf.org/html/rfc2047>), but they won't
+-- be decoded.