Merge p3yk branch with the trunk up to revision 45595. This breaks a fair
number of tests, all because of the codecs/_multibytecodecs issue described
here (it's not a Py3K issue, just something Py3K discovers):
http://mail.python.org/pipermail/python-dev/2006-April/064051.html

Hye-Shik Chang promised to look for a fix, so no need to fix it here. The
tests that are expected to break are:

test_codecencodings_cn
test_codecencodings_hk
test_codecencodings_jp
test_codecencodings_kr
test_codecencodings_tw
test_codecs
test_multibytecodec

This merge fixes an actual test failure (test_weakref) in this branch,
though, so I believe merging is the right thing to do anyway.
diff --git a/Lib/copy_reg.py b/Lib/copy_reg.py
index 169520d..f4661ed 100644
--- a/Lib/copy_reg.py
+++ b/Lib/copy_reg.py
@@ -111,8 +111,19 @@
         # Slots found -- gather slot names from all base classes
         for c in cls.__mro__:
             if "__slots__" in c.__dict__:
-                names += [name for name in c.__dict__["__slots__"]
-                               if name not in ("__dict__", "__weakref__")]
+                slots = c.__dict__['__slots__']
+                # if class has a single slot, it can be given as a string
+                if isinstance(slots, basestring):
+                    slots = (slots,)
+                for name in slots:
+                    # special descriptors
+                    if name in ("__dict__", "__weakref__"):
+                        continue
+                    # mangled names
+                    elif name.startswith('__') and not name.endswith('__'):
+                        names.append('_%s%s' % (c.__name__, name))
+                    else:
+                        names.append(name)
 
     # Cache the outcome in the class if at all possible
     try: