Fixed SF bug #663074. The codec system was using global static
variables to store internal data. As a result, any atempts to use the
unicode system with multiple active interpreters, or successive
interpreter executions, would fail.

Now that information is stored into members of the PyInterpreterState
structure.
diff --git a/Misc/NEWS b/Misc/NEWS
index 987ded7..baa3da3 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -29,6 +29,11 @@
 - On 64-bit systems, a dictionary could contain duplicate long/int keys
   if the key value was larger than 2**32.  See SF bug #689659.
 
+- Fixed SF bug #663074. The codec system was using global static
+  variables to store internal data. As a result, any atempts to use the
+  unicode system with multiple active interpreters, or successive
+  interpreter executions, would fail.
+
 Extension modules
 -----------------