Index: Lib/fnmatch.py
===================================================================
--- Lib/fnmatch.py	(révision 65973)
+++ Lib/fnmatch.py	(copie de travail)
@@ -11,6 +11,7 @@
 """
 
 import re
+import sys
 
 __all__ = ["filter", "fnmatch","fnmatchcase","translate"]
 
@@ -45,15 +46,25 @@
     if not pat in _cache:
         res = translate(pat)
         _cache[pat] = re.compile(res)
+    else:
+        res = None
     match=_cache[pat].match
-    if os.path is posixpath:
-        # normcase on posix is NOP. Optimize it away from the loop.
-        for name in names:
-            if match(name):
+    match_bytes = None
+    for name in names:
+        if isinstance(name, bytes):
+            if not match_bytes:
+                # create match regex for bytes string
+                charset = sys.getfilesystemencoding()
+                pat = pat.encode(charset)
+                if not pat in _cache:
+                    if res is None:
+                        res = translate(pat)
+                    res = res.encode(charset)
+                    _cache[pat] = re.compile(res)
+                match_bytes = _cache[pat].match
+            if match_bytes(os.path.normcase(name)):
                 result.append(name)
-    else:
-        for name in names:
-            if match(os.path.normcase(name)):
+        elif match(os.path.normcase(name)):
                 result.append(name)
     return result
 
Index: Lib/test/test_fnmatch.py
===================================================================
--- Lib/test/test_fnmatch.py	(révision 65973)
+++ Lib/test/test_fnmatch.py	(copie de travail)
@@ -2,8 +2,9 @@
 
 from test import support
 import unittest
+import sys
 
-from fnmatch import fnmatch, fnmatchcase
+from fnmatch import fnmatch, fnmatchcase, filter
 
 
 class FnmatchTestCase(unittest.TestCase):
@@ -37,6 +38,11 @@
         check('a', r'[!\]')
         check('\\', r'[!\]', 0)
 
+    def test_filter_bytes(self):
+        charset = sys.getfilesystemencoding()
+        abc = "abc".encode(charset)
+        names = ["abc", abc]
+        self.assertEqual(filter(names, "*"), names)
 
 def test_main():
     support.run_unittest(FnmatchTestCase)