diff --git a/flask_socketio/__init__.py b/flask_socketio/__init__.py
index cb27b88f..dcbd2585 100644
--- a/flask_socketio/__init__.py
+++ b/flask_socketio/__init__.py
@@ -331,6 +331,11 @@ def on_namespace(self, namespace_handler):
         else:
             self.namespace_handlers.append(namespace_handler)
 
+        # if the namespace handler has an on_error method then register it
+        error_handler = getattr(namespace_handler, 'on_error', None)
+        if error_handler is not None:
+            self.on_error(namespace_handler.namespace)(error_handler)
+
     def emit(self, event, *args, **kwargs):
         """Emit a server generated SocketIO event.
 
diff --git a/test_socketio.py b/test_socketio.py
index 34ad8deb..fa620817 100755
--- a/test_socketio.py
+++ b/test_socketio.py
@@ -226,6 +226,18 @@ def on_other_custom_event(self, data):
         request_event_data = request.event
         emit('my custom response', data)
 
+    def on_error_testing(self, data):
+        raise AssertionError()
+
+    def on_error(self, value):
+        if isinstance(value, AssertionError):
+            global error_testing_namespace_class_based
+            error_testing_namespace_class_based = True
+        else:
+            raise value
+        return value
+
+
 
 socketio.on_namespace(MyNamespace('/ns'))
 
@@ -615,6 +627,14 @@ def test_request_event_data_class_based(self):
         expected_data = {'message': 'other_custom_event', 'args': ('foo',)}
         self.assertEqual(request_event_data, expected_data)
 
+    def test_error_handling_class_based(self):
+        client = socketio.test_client(app, namespace='/ns')
+        client.get_received('/ns')
+        global error_testing_namespace_class_based
+        error_testing_namespace_class_based = False
+        client.emit('error_testing', 'testing', namespace='/ns')
+        self.assertTrue(error_testing_namespace_class_based)
+
     def test_delayed_init(self):
         app = Flask(__name__)
         socketio = SocketIO(allow_upgrades=False, json=flask_json)