diff -rup Python-2.5.1-orig/Python/codecs.c Python-2.5.1/Python/codecs.c
--- Python-2.5.1-orig/Python/codecs.c	2006-06-23 17:16:18.000000000 -0400
+++ Python-2.5.1/Python/codecs.c	2007-10-30 12:51:10.000000000 -0400
@@ -45,6 +45,11 @@ int PyCodec_Register(PyObject *search_fu
     return -1;
 }
 
+/* isupper() forced into the ASCII Locale */
+#define ascii_isupper(x) (((x) >= 0x41) && ((x) <= 0x5A))
+/* tolower() forced into the ASCII Locale */
+#define ascii_tolower(x) (ascii_isupper(x) ? ((x) + 0x20) : (x))
+
 /* Convert a string to a normalized Python string: all characters are
    converted to lower case, spaces are replaced with underscores. */
 
@@ -70,7 +75,7 @@ PyObject *normalizestring(const char *st
         if (ch == ' ')
             ch = '-';
         else
-            ch = tolower(Py_CHARMASK(ch));
+            ch = ascii_tolower(Py_CHARMASK(ch));
 	p[i] = ch;
     }
     return v;
Only in Python-2.5.1/Python: codecs.c~