diff -r 30425672adf7 paste/auth/cookie.py
--- a/paste/auth/cookie.py	Wed Jun 23 17:15:45 2010 -0500
+++ b/paste/auth/cookie.py	Mon Aug 02 20:06:43 2010 -0700
@@ -62,7 +62,7 @@
 _decode = [(v, k) for (k, v) in _encode]
 _decode.reverse()
 def encode(s, sublist = _encode):
-    return reduce((lambda a, (b, c): a.replace(b, c)), sublist, str(s))
+    return reduce((lambda a, b: a.replace(b[0], b[1])), sublist, str(s))
 decode = lambda s: encode(s, _decode)
 
 class CookieTooLarge(RuntimeError):