static byte[] EncodeUnstructuredHeader (ParserOptions options, FormatOptions format, Encoding charset, string field, string value)
{
if (format.International) {
var folded = Fold (format, field, value);
return Encoding.UTF8.GetBytes (folded);
}
var encoded = Rfc2047.EncodeText (format, charset, value);
return Rfc2047.FoldUnstructuredHeader (format, field, encoded);
}