http://www.rfc-editor.org/rfc/rfc1557.txt
RFC 1557: Korean Character Encoding for Internet Messages, U. Choi, K. Chon, H. Park1993-12-01T23:00:00-00:00This document describes the encoding method being used to represent Korean characters in both header and body part of the Internet mail messages [RFC822]. This encoding method was specified in 1991, and has since then been used. It has now widely being used in Korean IP networks. This memo provides information for the Internet community. This memo does not specify an Internet standard of any kind.