Cannot set bytes in UDH header larger than 127 about node-smpp HOT 1 CLOSED

var pdu = new smpp.PDU('deliver_sm', {
    message_payload: {
        udh: new Buffer([5, 0, 3, 227, 2, 2]),
        message: Array(153).join("B")
    }
});

var smpp = require('smpp');
var assert = require('assert');
// UDH header
var session_id = new Buffer([5, 0, 3, 227]);

var message_part1 = new Buffer([2, 1]);
var message_part2 = new Buffer([2, 2]);

// message parts
var message1 = Array(153).join("A")
var message2 = Array(153).join("B")

var part1 = new Buffer(message1);
var part2 = new Buffer(message2);

// Setting message payload field inside the deliver_sm function
var bufferArr = [session_id, message_part2, part2];
var concatenatedBuf = Buffer.concat(bufferArr);

var pdu = new smpp.PDU('deliver_sm', {
    message_payload: concatenatedBuf
});

var b = pdu.toBuffer();

smpp.tlvs.message_payload.filter = null;
var pdu = new smpp.PDU('deliver_sm', {
    message_payload: concatenatedBuf
});

var b2 = pdu.toBuffer();

assert.deepEqual(b,b2);