diff --git a/Lib/Cookie.py b/Lib/Cookie.py
index 6a45d9b..3b2592a 100644
--- a/Lib/Cookie.py
+++ b/Lib/Cookie.py
@@ -222,7 +222,7 @@
 except ImportError:
     from pickle import dumps, loads
 
-import re
+import re, warnings
 
 __all__ = ["CookieError","BaseCookie","SimpleCookie","SerialCookie",
            "SmartCookie","Cookie"]
@@ -682,6 +682,11 @@
     Note: HTTP has a 2k limit on the size of a cookie.  This class
     does not check for this limit, so be careful!!!
     """
+    def __init__(self, input=None):
+        warnings.warn("SerialCookie class is insecure; do not use it",
+                      DeprecationWarning)
+        BaseCookie.__init__(self, input)
+    # end __init__
     def value_decode(self, val):
         # This could raise an exception!
         return loads( _unquote(val) ), val
@@ -702,6 +707,11 @@
     Note: HTTP has a 2k limit on the size of a cookie.  This class
     does not check for this limit, so be careful!!!
     """
+    def __init__(self, input=None):
+        warnings.warn("Cookie/SmartCookie class is insecure; do not use it",
+                      DeprecationWarning)
+        BaseCookie.__init__(self, input)
+    # end __init__
     def value_decode(self, val):
         strval = _unquote(val)
         try: