Ticket #1980: datefield_patch.diff

db/models/fields/__init__.py

@@ -439 +439 @@
 
     def get_db_prep_save(self, value):
         # Casts dates into string format for entry into database.
-        if value is not None:
+        if isinstance(value, datetime.date):
             value = value.strftime('%Y-%m-%d')
+        else:
+            value = None
         return Field.get_db_prep_save(self, value)
 
     def get_manipulator_field_objs(self):