Index: Lib/posixpath.py
===================================================================
--- Lib/posixpath.py	(révision 65973)
+++ Lib/posixpath.py	(copie de travail)
@@ -11,6 +11,7 @@
 """
 
 import os
+import sys
 import stat
 import genericpath
 from genericpath import *
@@ -59,14 +60,23 @@
     """Join two or more pathname components, inserting '/' as needed.
     If any component is an absolute path, all previous path components
     will be discarded."""
+    use_bytes = any( isinstance(part, bytes) for part in (a,)+p )
     path = a
+    sep = '/'
+    if use_bytes:
+        charset = sys.getfilesystemencoding()
+        sep = sep.encode(charset)
+        if use_bytes and isinstance(path, str):
+            path = path.encode(charset)
     for b in p:
-        if b.startswith('/'):
+        if use_bytes and isinstance(b, str):
+            b = b.encode(charset)
+        if b.startswith(sep):
             path = b
-        elif path == '' or path.endswith('/'):
+        elif path == '' or path.endswith(sep):
             path +=  b
         else:
-            path += '/' + b
+            path += sep + b
     return path