Index: Lib/locale.py
===================================================================
--- Lib/locale.py	(revision 73904)
+++ Lib/locale.py	(working copy)
@@ -567,10 +567,22 @@
                 except Error:
                     pass
                 result = nl_langinfo(CODESET)
+                if not result and sys.platform == 'darwin':
+                    # nl_langinfo can return an empty string
+                    # when the setting has an invalid value.
+                    # Default to UTF-8 in that case because
+                    # UTF-8 is the default charset on OSX and
+                    # returning nothing will crash the 
+                    # interpreter.
+                    result = 'UTF-8'
+
                 setlocale(LC_CTYPE, oldloc)
                 return result
             else:
-                return nl_langinfo(CODESET)
+                if not result and sys.platform == 'darwin':
+                    # See above for explanation
+                    result = 'UTF-8'
+                result = nl_langinfo(CODESET)
 
 
 ### Database