@Override
    public void transferByteRangeTo(Output output, boolean utf8String, int fieldNumber, boolean repeated)
            throws IOException
    {

        if (utf8String)
        {
            output.writeString(fieldNumber, readString(), repeated);
        }
        else
        {
            output.writeByteArray(fieldNumber, readByteArray(), repeated);
        }

    }
Use another parser in msgpack input
protostuff-msgpack/src/main/java/io/protostuff/MsgpackInput.java