diff --git a/lib/connect/ws.js b/lib/connect/ws.js
index 81e91b7af..e5d6f0440 100644
--- a/lib/connect/ws.js
+++ b/lib/connect/ws.js
@@ -43,7 +43,7 @@ function buildBuilderBrowser(mqttClient, opts) {
     , port = opts.port
     , url = opts.protocol + '://' + host + ':' + opts.port
 
-  return websocket(url);
+  return websocket(url, 'mqttv3.1');
 }
 
 if (process.title !== 'browser') {
diff --git a/test/browser/server.js b/test/browser/server.js
index 46db1adbc..d395285c3 100644
--- a/test/browser/server.js
+++ b/test/browser/server.js
@@ -98,6 +98,10 @@ function start(port, done) {
   var wss = new WebSocketServer({server: server});
 
   wss.on('connection', function(ws) {
+    if (ws.protocol !== 'mqttv3.1') {
+      return ws.end();
+    }
+
     var stream = websocket(ws);
     var connection = new Connection(stream);
     handleClient(connection);
@@ -120,6 +124,6 @@ if (require.main === module) {
       console.error(err);
       return;
     }
-    console.log('tunnelled server started on port', port);
+    console.log('tunnelled server started on port', process.env.PORT || process.env.ZUUL_PORT);
   });
 }