diff --git a/hexlib/db.py b/hexlib/db.py
index ff3c441..827c708 100644
--- a/hexlib/db.py
+++ b/hexlib/db.py
@@ -160,6 +160,8 @@ def _sqlite_type(value):
 def _serialize(value):
     if isinstance(value, bytes):
         return base64.b64encode(value)
+    if value is None:
+        return None
     return str(value)
 
 
diff --git a/setup.py b/setup.py
index 2cee2bf..8362588 100644
--- a/setup.py
+++ b/setup.py
@@ -2,7 +2,7 @@ from setuptools import setup
 
 setup(
     name="hexlib",
-    version="1.20",
+    version="1.21",
     description="Misc utility methods",
     author="simon987",
     author_email="me@simon987.net",
diff --git a/test/test_PersistantState.py b/test/test_PersistantState.py
index c10937b..1ac9696 100644
--- a/test/test_PersistantState.py
+++ b/test/test_PersistantState.py
@@ -47,3 +47,17 @@ class TestPersistentState(TestCase):
         val["id"] = 1
 
         self.assertDictEqual(val, s["a"][1])
+
+    def test_none(self):
+        s = PersistentState()
+
+        val = {"a": 1, "b": None}
+        s["a"][1] = val
+        s["a"][1] = {
+            "a": None
+        }
+
+        val["a"] = None
+        val["id"] = 1
+
+        self.assertDictEqual(val, s["a"][1])