diff --git a/lib/index.js b/lib/index.js
index d3198b7..8fa505d 100644
--- a/lib/index.js
+++ b/lib/index.js
@@ -21,19 +21,39 @@ function noQsMethod(options) {
     socket.on('authenticate', function (data) {
       clearTimeout(auth_timeout);
       jwt.verify(data.token, options.secret, options, function(err, decoded) {
+        // error handler
+        var onError = function(err, code) {
+          if (err) {
+            code = code || 'unknown';
+            var error = new UnauthorizedError(code, {
+              message: (Object.prototype.toString.call(err) === '[object Object]' && err.message) ? err.message : err
+            });
+            socket.emit('unauthorized', error, function() {
+              socket.disconnect('unauthorized');
+            });
+            return; // stop logic, socket will be close on next tick
+          }
+        };
+
         if (err) {
-          socket.emit('unauthorized', err, function() {
-            socket.disconnect('unauthorized');
-          });
-          return; // stop logic, socket will be close on next tick
+          return onError(err, 'invalid_token');
         }
 
-        socket.decoded_token = decoded;
-        socket.emit('authenticated');
-        if (server.$emit) {
-          server.$emit('authenticated', socket);
+        // success handler
+        var onSuccess = function(){
+          socket.decoded_token = decoded;
+          socket.emit('authenticated');
+          if (server.$emit) {
+            server.$emit('authenticated', socket);
+          } else {
+            server.server.sockets.emit('authenticated', socket);
+          }
+        };
+
+        if(options.additional && typeof options.additional === 'function') {
+          options.additional(decoded, onSuccess, onError);
         } else {
-          server.server.sockets.emit('authenticated', socket);
+          onSuccess();
         }
       });
     });