MQTT client and HTTP module don't work together?

@Gordon I've posted some main parts of my code base. Hope this helps!

var wifi,
    wifiAPs = {},
    f = new (require("FlashEEPROM"))(),
    apServer,
    isProduction = true; // use this for debugging

function clog(s) {
  console.log(s);
}

/**
 * the MQTT broker server configurations
 */
var server = '192.168.1.14', // the ip of MQTT broker
    options = {
        client_id : UUID,
        //keep_alive: 60, // keep alive time in seconds
        port: 1883, // port number
        clean_session: true,
        username: "username", // name for auth that happens in the broker server
        password: "password",  // pwd for auth that happens in the broker server
        protocol_name: "MQTT", // or MQIsdp, etc..
        protocol_level: 4, // protocol level
    },
    client = require("MQTT").create(server, options /*optional*/);


/**
 * throwing error exceptions
 */
function throwError(err) {
    if (err) {
        progress = false;
        throw err;
    }
}

/**
 * Temporary server to collect the WiFi credentials like SSID, pwd etc
 * @method hsInit
 */
function hsInit() {
    apServer = require("http").createServer(hsRouter).l­isten(80);
}

/**
 * all the requests will be routed thro this
 * @method hsRouter
 */
function hsRouter(req, res) {
    getIndexHTML(req, res);
}

/**
 * index/home page of the Hula Server where we collect the WiFi credentials
 * @method getIndexHTML
 */
function getIndexHTML(req, res) {
    var pURL = url.parse(req.url, true);
    if (req.method === 'POST') {
        var postData = '',
            parsedData;

        req.on('data', function(d) {
            postData += d;
        });

        req.on('end', function(d) {
            parsedData = parseQuery(postData);
            clog(parsedData);

            // clear absolutely everything out of memory
            f.erase();

            // if there is a WiFi SSID given (required)
            if (parsedData.ap) {
                f.write(0, parsedData.ap);   
                clog(E.toString(f.read(0)));
            }

             // if there is a WiFi PWD given (required)

            // lets setup as we got the WiFi creds
            apServer.close();
            sTHandlerSetup = setTimeout(setup, 5000);
        });
    }

    // default/index route to display the web page
    if (pURL.pathname == '/') {

        // the HTML page that collects the WiFi creds
        res.writeHead(200, {'Content-Type': 'text/html'});
        // HTML Form to collect the required info 
        res.end('</body></html>'); 
    }
}


/**
 * initiate the required functions while booting the pico
 * @method onInit
 */
function onInit() {
    var setWatchId,
        pTime;

    // the external button for setting up 
    pinMode(B3, "input_pulldown");
    setWatchId = setWatch(function(e) {
        pTime = e.time - e.lastTime;

        // do not accept if it happens within 2 secs
        if(!progress && (isNaN(pTime) || pTime > 2)) {
            clearWatch(setWatchId);
            clog('Got you! Hang on! Im booting up.');
            progress = true;
            setup();
        }
    }, B3, { repeat: true, debounce : 150, edge: "rising" });
}

function setup() {

    if (sTHandlerSetup) {
      clog('clearing the setup timeout ...');
      clearTimeout(sTHandlerSetup);
    }
    Serial2.setup(115200, { rx: A3, tx : A2 });
    Serial2.removeAllListeners();
    wifi = require("ESP8266WiFi_0v25").connect(Seri­al2, function(err) {
        throwError(err);

        // reset the n/w before the connection
        wifi.reset(function(err) {
            throwError(err);
            // SSID, Access Point PWD, Email id, Token Details, Session Token
            var apSSID = typeof f.read(0) !== 'undefined' ? E.toString(f.read(0)) : '',
                apPWD = typeof f.read(1) !== 'undefined' ? E.toString(f.read(1)) : '';

            if (apSSID) {
                wifi.connect(apSSID, apPWD, function(err) {
                    throwError(err);
                    clog('Device is successfully connected to the WiFi.');
                    progress = false;
                    var sTHandlerMQTT;

                    sTHandlerMQTT = setTimeout(function() {
                        clog('clearing the MQTT timeout ...');
                        clearTimeout(sTHandlerMQTT);

                        // MQTT starts here
                        client.connect();

                        // MQTT: if there is any error 
                        client.on('error', function () {
                            clog('connection to the MQTT broker server failed');
                        });

                        // MQTT: while connecting
                        client.on('connected', function () {
                            clog('MQTT connected ...');
                        });

                        // MQTT: watching out for the messages that come in from the MQTT broker
                        client.on('message', function (topic, message) {
                            // logic for handling the messages
                        });

                        // in case, the MQTT broker server is down, reconnect
                        client.on('disconnected', function() {
                            clog("MQTT disconnected... reconnecting.");

                            // reconnect 3 times in every 5s
                            // 4 times in every 15s and 10 times in every 60s
                            client.connect();
                        });
                    }, 3000);
                });
            } else {

                // only if there is any WiFi SSID (Service Set IDentifier) in the EEPROM memory
                new Promise(function(resolve, reject) {

                    wifi.getAPs(function(err, aps) { 
                        for (var i in aps) {
                            for (var j in aps[i]) {
                                wifiAPs[aps[i][j]] = aps[i];
                                break;
                            }
                        }
                        resolve();
                    });
                }).then(function () {

                    // setup the WiFi access point
                    var SSID = 'sureshkm',
                        pwd = 'password';

                    wifi.createAP(SSID, pwd, 5, 'wpa_wpa2_psk', function(err) {
                        throwError(err);
                        clog('WiFi access point is successfully created.'); 
                    });

                    hsInit();
                }, function(err) {
                    throwError(new Error('Failed to collect the WiFi APs'));
                });
            }
        });
    });
}

// save the program into the micro controller 
save();