diff -r cccacbfa6eb7 Lib/distutils/tests/test_sdist.py
--- a/Lib/distutils/tests/test_sdist.py	Sun Apr 24 22:17:32 2011 +0800
+++ b/Lib/distutils/tests/test_sdist.py	Sun Apr 24 22:51:46 2011 +0800
@@ -47,13 +47,13 @@
 README
 inroot.txt
 setup.py
-data%(sep)sdata.dt
-scripts%(sep)sscript.py
-some%(sep)sfile.txt
-some%(sep)sother_file.txt
-somecode%(sep)s__init__.py
-somecode%(sep)sdoc.dat
-somecode%(sep)sdoc.txt
+data/data.dt
+scripts/script.py
+some/file.txt
+some/other_file.txt
+somecode/__init__.py
+somecode/doc.dat
+somecode/doc.txt
 """
 
 class SDistTestCase(PyPIRCCommandTestCase):
@@ -233,7 +233,7 @@
         f = open(join(self.tmp_dir, 'MANIFEST'))
         try:
             manifest = f.read()
-            self.assertEqual(manifest, MANIFEST % {'sep': '/'})
+            self.assertEqual(manifest, MANIFEST)
         finally:
             f.close()
 
@@ -430,20 +430,20 @@
         cmd.ensure_finalized()
         cmd.run()
         
-        f = open(cmd.manifest)
+        # always use slash character ('/') as separator
         MANIFEST_STR = """\
         # file GENERATED by distutils, do NOT edit
         README
         setup.py
-        somecode%(sep)s__init__.py
+        somecode/__init__.py
         """
+        
+        f = open(cmd.manifest)
         try:
             manifest = [line.strip() for line in f.read().split('\n')
                         if line.strip() != '']
             
-            # always use slash character ('/') as separator
-            manifest_slash = [line.strip() for line in 
-                                (MANIFEST_STR % {'sep': '/'}).split('\n')
+            manifest_slash = [line.strip() for line in MANIFEST_STR.split('\n')
                                 if line.strip() != '']
             self.assertEqual(manifest, manifest_slash)
         finally:
@@ -458,16 +458,19 @@
         cmd.ensure_finalized()
         # cmd will run later, thus know what different thing happens
         
-        f = open(cmd.manifest,'w')#now, MANIFEST file is empty or not created
         MANIFEST_STR = """\
         README
         setup.py
-        somecode%(sep)s__init__.py
-        """
+        somecode/__init__.py
+        """        
+        
+        f = open(join(self.tmp_dir, 'MANIFEST'), 'w')
         try:
-            f.write(MANIFEST_STR % {'sep': '/'})
-            filelist = [line.strip() for line in (MANIFEST_STR % {'sep': '/'})\
-                        .split('\n') if line.strip() !='']
+            # using a more easy way to test: directly write the string into 
+            # the MANIFEST file instead creating files
+            f.write(MANIFEST_STR)
+            filelist = [line.strip() for line in MANIFEST_STR.split('\n')
+                        if line.strip() !='']
             os.sep = '\\'
             cmd.run()# cmd run now
             filelist_generated = [line.strip().replace('\\','/') for line in \