Note the Unicode changes from SF patch #470578.

Misc/NEWS

 What's New in Python 2.2b1?
-Release date: 28-Sep-2100
+Release date: 19-Oct-2001
 ===========================
 
 Type/class unification and new-style classes
@@ -40,6 +40,11 @@ Core and builtins
   A bug which could allow a core dump when binary operations involved
   proxy reference has been fixed.
 
+- unicode(obj) now behaves more like str(obj), accepting arbitrary
+  objects, and calling a __unicode__ method if it exists.
+  unicode(obj, encoding) and unicode(obj, encoding, errors) still
+  require an 8-bit string argument.
+
 Extension modules
 
 - thread.start_new_thread() now returns the thread ID (previously None).
@@ -131,6 +136,9 @@ C API
   tested on Linux and Windows; other platforms please beware (and
   report any bugs or strange behavior).
 
+- PyUnicode_FromEncodedObject() no longer accepts Unicode objects as
+  input.
+
 New platforms
 
 Tests