diff --git a/src/socketio/msgpack_packet.py b/src/socketio/msgpack_packet.py
index 2746263..6e86a72 100644
--- a/src/socketio/msgpack_packet.py
+++ b/src/socketio/msgpack_packet.py
@@ -5,13 +5,33 @@ from . import packet
 class MsgPackPacket(packet.Packet):
     uses_binary_events = False
 
+    def __init__(
+        self,
+        packet_type=packet.EVENT,
+        data=None,
+        namespace=None,
+        id=None,
+        binary=None,
+        encoded_packet=None,
+        dumps_default=None,
+        ext_hook=None,
+    ):
+        super().__init__(
+            packet_type, data, namespace, id, binary, encoded_packet
+        )
+        self.dumps_default = dumps_default
+        self.ext_hook = ext_hook
+
     def encode(self):
         """Encode the packet for transmission."""
-        return msgpack.dumps(self._to_dict())
+        return msgpack.dumps(self._to_dict(), default=self.dumps_default)
 
     def decode(self, encoded_packet):
         """Decode a transmitted package."""
-        decoded = msgpack.loads(encoded_packet)
+        if self.ext_hook is None:
+            decoded = msgpack.loads(encoded_packet)
+        else:
+            decoded = msgpack.loads(encoded_packet, ext_hook=self.ext_hook)
         self.packet_type = decoded['type']
         self.data = decoded.get('data')
         self.id = decoded.get('id')