Actualized descrintro.html URL.
diff --git a/README b/README
index 729b1d4..7baeb4b 100644
--- a/README
+++ b/README
@@ -91,7 +91,7 @@
 The best documentation for the new (in Python 2.2) type/class
 unification features is Guido's tutorial introduction, at
 
-    http://www.python.org/2.2/descrintro.html
+    http://www.python.org/2.2.1/descrintro.html
 
 
 Web sites