Index: codereview/models.py
===================================================================
--- codereview/models.py	(revision 103)
+++ codereview/models.py	(working copy)
@@ -62,7 +62,7 @@
 
   subject = db.StringProperty(required=True)
   description = db.TextProperty()
-  base = db.URLProperty()
+  base = None
   owner = db.UserProperty(required=True)
   created = db.DateTimeProperty(auto_now_add=True)
   modified = db.DateTimeProperty(auto_now=True)