--- a/mercurial/util.py	Fri Dec 16 21:09:40 2011 +0900
+++ b/mercurial/util.py	Fri Dec 16 21:09:41 2011 +0900
@@ -24,6 +24,9 @@
 else:
     import posix as platform
 
+platform.encodinglower = encoding.lower
+platform.encodingupper = encoding.upper
+
 cachestat = platform.cachestat
 checkexec = platform.checkexec
 checklink = platform.checklink