--- a/mercurial/merge.py	Thu Dec 15 16:18:10 2011 +0100
+++ b/mercurial/merge.py	Mon Dec 12 17:10:19 2011 +0900
@@ -7,7 +7,7 @@
 
 from node import nullid, nullrev, hex, bin
 from i18n import _
-import scmutil, util, filemerge, copies, subrepo, encoding
+import scmutil, util, filemerge, copies, subrepo
 import errno, os, shutil
 
 class mergestate(object):
@@ -100,7 +100,7 @@
     "check for case folding collisions in the destination context"
     folded = {}
     for fn in mctx:
-        fold = encoding.lower(fn)
+        fold = util.normcase(fn)
         if fold in folded:
             raise util.Abort(_("case-folding collision between %s and %s")
                              % (fn, folded[fold]))