diff --git a/lib/options.js b/lib/options.js
index ca6009b..1737484 100755
--- a/lib/options.js
+++ b/lib/options.js
@@ -258,13 +258,6 @@ function validate(opts, validationOptions) {
 
   var result = validator.validate(opts, '/Options', validationOptions);
 
-  // check empty interfaces
-  if (opts.hasOwnProperty('interfaces')) {
-    if (opts.interfaces.length === 0) {
-      result.addError('no interfaces were defined');
-    }
-  }
-
   // check required credentials
   if (opts.hasOwnProperty('interfaces')) {
     var hasCredentials = opts.hasOwnProperty('credentials');
diff --git a/lib/server.js b/lib/server.js
index b8d9f1d..711d31b 100755
--- a/lib/server.js
+++ b/lib/server.js
@@ -162,6 +162,7 @@ function Server(opts, callback) {
   // initialize servers list
   this.servers = [];
 
+
   steed.series([
 
     // steed.series: wait for ascoltatore
@@ -236,7 +237,6 @@ function Server(opts, callback) {
     }
   });
 
-
   that.on("clientConnected", function(client) {
     if(that.modernOpts.publishNewClient) {
       that.publish({
@@ -609,10 +609,17 @@ Server.prototype.close = function(callback) {
  *
  * @api public
  * @param {HttpServer} server
+ * @param {String} path
  */
-Server.prototype.attachHttpServer = function(server) {
+Server.prototype.attachHttpServer = function(server, path) {
   var that = this;
-  ws.createServer({ server: server }, function(stream) {
+
+  var opt = { server: server };
+  if (path) {
+    opt.path = path;
+  }
+  
+  ws.createServer(opt, function(stream) {
     var conn = new Connection(stream);
     new Client(conn, that);
   });
diff --git a/package.json b/package.json
index 7783fc9..e496049 100644
--- a/package.json
+++ b/package.json
@@ -48,6 +48,7 @@
   "author": "Matteo Collina <hello@matteocollina.com>",
   "license": "MIT",
   "devDependencies": {
+    "browserify": "~13.0.0",
     "chai": "^3.5.0",
     "coveralls": "~2.11.1",
     "dox-foundation": "~0.5.4",
@@ -62,9 +63,9 @@
     "sinon-chai": "~2.8.0",
     "supertest": "~1.2.0",
     "tmp": "0.0.24",
-    "browserify": "~13.0.0",
     "uglify-js": "^2.4.16",
-    "underscore": "^1.7.0"
+    "underscore": "^1.7.0",
+    "ws": "^1.0.1"
   },
   "dependencies": {
     "array-from": "^2.1.1",
diff --git a/test/abstract_server.js b/test/abstract_server.js
index 2be95b5..8ac41d8 100644
--- a/test/abstract_server.js
+++ b/test/abstract_server.js
@@ -41,9 +41,9 @@ module.exports = function(moscaSettings, createConnection) {
     });
 
     function finish () {
-      client.removeListener('error', finish)
-      client.stream.removeListener('close', finish)
-      done()
+      client.removeListener('error', finish);
+      client.stream.removeListener('close', finish);
+      done();
     }
   }
 
diff --git a/test/server.js b/test/server.js
index 6e772a1..2ac1a83 100644
--- a/test/server.js
+++ b/test/server.js
@@ -174,7 +174,7 @@ describe("mosca.Server", function() {
     // Simulate a situation that it takes same time to do authorizeSubscribe.
     this.instance.authorizeSubscribe = function(client, topic, callback) {
       setTimeout(function(){
-        callback(null, true)
+        callback(null, true);
       }, 300);
     };
 
diff --git a/test/server_websocket_attach.js b/test/server_websocket_attach.js
new file mode 100644
index 0000000..3eed9bc
--- /dev/null
+++ b/test/server_websocket_attach.js
@@ -0,0 +1,201 @@
+var mqtt = require('mqtt');
+var websocket = require('ws');
+var http = require('http');
+
+var port = nextPort();
+var path = '/test';
+var mqttPath = '/mqttws';
+var mqttTopic = 'atopic';
+var ping = 'ping';
+var pong = 'pong';
+
+describe("mosca.Server - Mqtt-over-WS attached to existing http server", function() {
+  var server, mqttServ;
+
+  beforeEach(function(){
+    server = http.createServer();
+    mqttServ = new mosca.Server({interfaces:[]});
+  });
+
+  afterEach(function(){
+    server.close();
+  });
+
+  it("should not occupy 1883 port while attached to http server", function(done) {
+    mqttServ.attachHttpServer(server);
+    server.listen(1883, done);
+  });
+
+  it("should be able to do mqtt over WebSocket", function(done) {
+    mqttServ.attachHttpServer(server);
+    server.listen(port, function(){
+      var client = mqtt.connect('ws://localhost:' + port);
+      client.subscribe(mqttTopic);
+      client.on("message", function(topic, payload) {
+        expect(topic).to.equal(mqttTopic);
+        expect(payload.toString()).to.equal(ping);
+        done();
+      });
+      client.publish(mqttTopic, ping);
+    });
+  });
+
+  it("should be able to do mqtt over WebSocket on specific path", function(done) {
+    mqttServ.attachHttpServer(server, mqttPath);
+    server.listen(port, function(){
+      var client = mqtt.connect('ws://localhost:' + port + mqttPath);
+      client.subscribe(mqttTopic);
+      client.on("message", function(topic, payload) {
+        expect(topic).to.equal(mqttTopic);
+        expect(payload.toString()).to.equal(ping);
+        done();
+      });
+      client.publish(mqttTopic, ping);
+    });
+  });
+
+  it("should not be able to do mqtt over WebSocket on different path", function(done) {
+    mqttServ.attachHttpServer(server, mqttPath);
+    server.listen(port, function(){
+      var client = mqtt.connect('ws://localhost:' + port + '/junk');
+      client.subscribe(mqttTopic);
+      var failed = false;// ensuring done is called once
+      client.on("message", function(topic, payload) {
+        failed = true;
+        done(failed);
+      });
+      client.publish(mqttTopic, ping);
+      setTimeout(function(){
+        if (!failed){
+          done();
+        }
+      }, 3000);
+    });
+  });
+
+  it("should not be able to do mqtt over WebSocket on root path", function(done) {
+    mqttServ.attachHttpServer(server, mqttPath);
+    server.listen(port, function(){
+      var client = mqtt.connect('ws://localhost:' + port);
+      client.subscribe(mqttTopic);
+      var failed = false;
+      client.on("message", function(topic, payload) {
+        failed = true;
+        done(failed);
+      });
+      client.publish(mqttTopic, ping);
+      setTimeout(function(){
+        if (!failed){
+          done();
+        }
+      }, 2000);
+    });
+  });
+});
+
+describe("mosca.Server - Websocket and Mqtt-over-WS attached to the same http server", function() {
+  var server, mqttServ, wss;
+
+  beforeEach(function(){
+    server = http.createServer();
+    mqttServ = new mosca.Server({interfaces:[]});
+
+    wss = new websocket.Server({
+      server: server,
+      path: path,
+      perMessageDeflate: false
+    });
+  });
+
+  afterEach(function(){
+    server.close();
+  });
+
+  it("ws client should not connect when mqtt is attached to http server without path", function(done) {
+    mqttServ.attachHttpServer(server);
+    server.listen(port, function(){
+      var ws = new websocket('ws://localhost:' + port + path, {
+        perMessageDeflate: false
+      });
+
+      ws.on('error', function(e) {
+        expect(e).to.not.be.undefined;
+        done();
+      });
+    });
+  });
+
+  it("ws client should be able to connect when specific path is used", function(done) {
+    mqttServ.attachHttpServer(server, mqttPath);
+    wss.on('connection', function(conn){
+      conn.on('message', function(msg){
+        expect(msg).to.equal(ping);
+        conn.send(pong);
+      });
+    });
+
+    server.listen(port, function(){
+      var ws = new websocket('ws://localhost:' + port + path, {
+        perMessageDeflate: false
+      });
+
+      ws.on('open', function(){
+        ws.send(ping);
+      });
+
+      ws.on('message', function(msg){
+        expect(msg).to.equal(pong);
+        done();
+      });
+    });
+  });
+
+  it("mqtt client should be able to connect as well", function(done) {
+    mqttServ.attachHttpServer(server, mqttPath);
+    server.listen(port, function(){
+      var client = mqtt.connect('ws://localhost:' + port + mqttPath);
+      client.subscribe(mqttTopic);
+      client.on("message", function(topic, payload) {
+        expect(topic).to.equal(mqttTopic);
+        expect(payload.toString()).to.equal(ping);
+        done();
+      });
+      client.publish(mqttTopic, ping);
+    });
+  });
+
+  it("both ws and mqtt client should be able to connect at the same time", function(done) {
+    mqttServ.attachHttpServer(server, mqttPath);
+    wss.on('connection', function(conn){
+      conn.on('message', function(msg){
+        expect(msg).to.equal(ping);
+        conn.send(pong);
+      });
+    });
+
+    server.listen(port, function(){
+      var client = mqtt.connect('ws://localhost:' + port + mqttPath);
+      var ws = new websocket('ws://localhost:' + port + path, {
+        perMessageDeflate: false
+      });
+
+      client.on('connect', function () {
+        client.subscribe(mqttTopic);
+        setTimeout(function(){// wait for ws to connect
+          ws.send(ping);
+        }, 2000);
+      });
+
+      ws.on('message', function(msg){
+        expect(msg).to.equal(pong);
+        client.publish(mqttTopic, ping);
+      });
+
+      client.on("message", function(topic, payload) {
+        expect(topic).to.equal(mqttTopic);
+        expect(payload.toString()).to.equal(ping);
+        done();
+      });
+    });
+  });
+});