# File lib/action_mailer/vendor/tmail/utils.rb, line 207 def decode_RFC2231( str ) m = RFC2231_ENCODED.match(str) or return str begin NKF.nkf(NKF_FLAGS[$KCODE], m.post_match.gsub(/%[\da-f]{2}/in) {|s| s[1,2].hex.chr }) rescue m.post_match.gsub(/%[\da-f]{2}/in, "") end end