diff --git a/socketIO_client/__init__.py b/socketIO_client/__init__.py
index 4552103..05492d9 100644
--- a/socketIO_client/__init__.py
+++ b/socketIO_client/__init__.py
@@ -444,7 +444,7 @@ class SocketIO(object):
         _log.debug("[event] %s (%s)" % (repr(event), repr(args)));
 
         if packet.payload.id is not None:
-            args.append(self._prepare_to_send_ack(path, packet_id))
+            args.append(self._prepare_to_send_ack(packet.payload.path, packet.payload.id))
         find_event_callback(event)(*args);
 
     def _on_ack(self, packet, find_event_callback):
diff --git a/socketIO_client/parser.py b/socketIO_client/parser.py
index 3e657d0..8fe06b1 100644
--- a/socketIO_client/parser.py
+++ b/socketIO_client/parser.py
@@ -32,6 +32,27 @@ class Packet():
     def __str__(self):
         return "PACKET{type: " + str(self.type) + ", payload: " + str(self.payload) + "}";
 
+    def encode_as_string(self, for_websocket = False):
+        data = "";
+        path = "";
+        if self.type == PacketType.MESSAGE:
+            data = self.payload.encode_as_string();
+            path = self.payload.path;
+        else:
+            data = self.payload;           
+
+        code_length = len(str(self.type));
+        data_length = len(data);
+        length = code_length + data_length;
+
+        encoded = "";
+        if for_websocket:
+            encoded = str(self.type) + str(data);
+        else:
+            encoded = str(length) + ":" + str(self.type) + str(data);
+ 
+        return encoded;
+
 class Message():
     def __init__(self, message_type, message, path = "", attachments = "", message_id = None):
         self.type = message_type;
@@ -67,15 +88,30 @@ class Message():
         
         Assumes the message payload will be dumped as a json string.
         """
+        data = json.dumps(self.message);
+        if self.id is not None:
+            data = str(self.id) + json.dumps(self.message);
+
         if self.path == "":
-            return str(self.type) + json.dumps(self.message);
-        return str(self.type) + self.path + "," + json.dumps(self.message);
+            return str(self.type) + data;
+        return str(self.type) + self.path + "," + data;
 
     def encode_as_string(self):
         """Same as the encode_as_string method except it doesn't encode things as a JSON string"""
+        data = self.message;
+        if self.id is not None:
+            data = str(self.id) + self.message;
+
         if self.path == "":
-            return str(self.type) + self.message;
-        return str(self.type) + self.path + "," + self.message;
+            return str(self.type) + data;
+        return str(self.type) + self.path + "," + data;
+
+def _is_integer(s):
+    try:
+        int(s);
+    except ValueError:
+        return False;
+    return True;
 
 def decode_message(payload):
     """ Decodes a message encoded via socket.io
@@ -112,11 +148,15 @@ def decode_message(payload):
                 i += len(path);
     
     if len(payload) > i:
-        # This is the same pecularity as above.
-        if "," in payload[i:]:
-            split_point = payload.index(",");
-            message_id = int(payload[i:split_point]);
-            i += split_point;
+        # This is another oddity. According to the socket.io-parser we
+        # need to loop over the next chars until we stop finding ints
+        # to determine if there is a message id.
+        message_id_str = "";
+        while _is_integer(payload[i]):
+            message_id_str += payload[i];
+            i += 1;
+        if message_id_str != "":
+            message_id = int(message_id_str);
 
     if len(payload) > i:
         message = payload[i:];
@@ -198,8 +238,3 @@ def encode_packet_string(code, path, data):
     """Encodes packet to be sent to socket.io server.
     """
 
-    code_length = len(str(code));
-    data_length = len(data);
-    length = code_length + data_length;
-
-    return str(length) + ":" + str(code) + str(data);
diff --git a/socketIO_client/transports.py b/socketIO_client/transports.py
index 32a03f1..65be157 100644
--- a/socketIO_client/transports.py
+++ b/socketIO_client/transports.py
@@ -1,7 +1,7 @@
 import json
 import logging
 import parser
-from parser import Message, MessageType, PacketType
+from parser import Message, Packet, MessageType, PacketType
 import re
 import requests
 import six
@@ -75,18 +75,16 @@ class _AbstractTransport(object):
         self.send_packet(PacketType.MESSAGE, path, message.encode_as_json(), callback)
 
     def ack(self, path, packet_id, *args):
-        packet_id = packet_id.rstrip('+')
-        data = '%s+%s' % (
-            packet_id,
-            json.dumps(args, ensure_ascii=False),
-        ) if args else packet_id
-        #self.send_packet(6, path, data)
+        _log.debug("[ack] Sending ACK for packet: %d" % packet_id);
+        message = Message(MessageType.ACK, "", path, "", packet_id);
+        packet = Packet(PacketType.MESSAGE, message);
+        self.send_engineio_packet(packet)
 
     def noop(self, path=''):
         self.send_packet(PacketType.NOOP, path)
 
     def send_packet(self, code, path='', data='', callback=None):
-        packet_text = parser.encode_packet_string(code, path, data);
+        packet_text = Packet(code, data).encode_as_string();
         self.send(packet_text)
         _log.debug('[packet sent] %s', packet_text)
 
@@ -140,11 +138,19 @@ class WebsocketTransport(_AbstractTransport):
     def connected(self):
         return self._connection.connected
 
-    def send_packet(self, code, path="", data='', callback=None):
-        packet_text = Message(code, data).encode_as_string();
+    def send_message(self, message, callback = None):
+        packet_text = message.encode_as_string();
         self.send(packet_text)
         _log.debug('[packet sent] %s', packet_text)
 
+    def send_engineio_packet(self, packet, callback=None):
+        packet_text = packet.encode_as_string(for_websocket = True);
+        self.send(packet_text)
+        _log.debug('[packet sent] %s', packet_text)
+
+    def send_packet(self, code, path="", data='', callback=None):
+        self.send_message(Message(code, data), callback);
+
     def send(self, packet_text):
         try:
             self._connection.send(packet_text)