diff --git a/bson/json_util.py b/bson/json_util.py
index 2862b439e..c1700d791 100644
--- a/bson/json_util.py
+++ b/bson/json_util.py
@@ -89,6 +89,7 @@ except ImportError:
 
 from bson import EPOCH_AWARE, RE_TYPE, SON
 from bson.binary import Binary
+from bson.bsonint64 import BSONInt64
 from bson.code import Code
 from bson.dbref import DBRef
 from bson.max_key import MaxKey
@@ -193,6 +194,10 @@ def object_hook(dct, compile_re=True):
         return Code(dct["$code"], dct.get("$scope"))
     if "$uuid" in dct:
         return uuid.UUID(dct["$uuid"])
+    if "$undefined" in dct:
+        return None
+    if "$numberLong" in dct:
+        return BSONInt64(dct["$numberLong"])
     return dct
 
 
diff --git a/test/test_json_util.py b/test/test_json_util.py
index 3fefa9ff5..263fa30e3 100644
--- a/test/test_json_util.py
+++ b/test/test_json_util.py
@@ -22,6 +22,7 @@ import uuid
 sys.path[0:0] = [""]
 
 from bson import json_util
+from bson.bsonint64 import BSONInt64
 from bson.binary import Binary, MD5_SUBTYPE, USER_DEFINED_SUBTYPE
 from bson.code import Code
 from bson.dbref import DBRef
@@ -202,6 +203,15 @@ class TestJsonUtil(unittest.TestCase):
         # Check order.
         self.assertEqual('{"$code": "return z", "$scope": {"z": 2}}', res)
 
+    def test_undefined(self):
+        json = '{"name": {"$undefined": true}}'
+        self.assertIsNone(json_util.loads(json)['name'])
+
+    def test_numberlong(self):
+        json = '{"weight": {"$numberLong": 65535}}'
+        self.assertEqual(json_util.loads(json)['weight'],
+                         BSONInt64(65535))
+
 
 class TestJsonUtilRoundtrip(IntegrationTest):