Index: Lib/http/server.py
===================================================================
--- Lib/http/server.py	(revision 86565)
+++ Lib/http/server.py	(working copy)
@@ -661,12 +661,17 @@
 
         """
         path = self.translate_path(self.path)
+        # We want to use an untranslated path here, but stripped of
+        # query parameters and fragments
+        stripped_path = self.path.split('?', 1)[0]
+        stripped_path = stripped_path.split('#', 1)[0]
+        suffix = self.path[len(stripped_path):]
         f = None
         if os.path.isdir(path):
-            if not self.path.endswith('/'):
+            if not stripped_path.endswith('/'):
                 # redirect browser - doing basically what apache does
                 self.send_response(301)
-                self.send_header("Location", self.path + "/")
+                self.send_header("Location", stripped_path + "/" + suffix)
                 self.end_headers()
                 return None
             for index in "index.html", "index.htm":
Index: Lib/test/test_httpservers.py
===================================================================
--- Lib/test/test_httpservers.py	(revision 86565)
+++ Lib/test/test_httpservers.py	(working copy)
@@ -209,6 +209,8 @@
         self.tempdir_name = os.path.basename(self.tempdir)
         with open(os.path.join(self.tempdir, 'test'), 'wb') as temp:
             temp.write(self.data)
+        with open(os.path.join(self.tempdir, 'test?foo'), 'wb') as temp:
+            temp.write(self.data)
 
     def tearDown(self):
         try:
@@ -249,6 +251,23 @@
                 response = self.request(self.tempdir_name + '/')
                 self.check_status_and_reason(response, 404)
                 os.chmod(self.tempdir, 0o755)
+        response = self.request(self.tempdir_name + '?foo')
+        self.check_status_and_reason(response, 301)
+        self.assertEqual(response.getheader('Location'), self.tempdir_name + '/?foo')
+        response = self.request(self.tempdir_name + '/?foo')
+        self.check_status_and_reason(response, 200)
+        response = self.request(self.tempdir_name + '/?foo/')
+        self.check_status_and_reason(response, 200)
+        response = self.request(self.tempdir_name + '?foo/')
+        self.check_status_and_reason(response, 301)
+        self.assertEqual(response.getheader('Location'), self.tempdir_name + '/?foo/')
+        response = self.request(self.tempdir_name + '#foo')
+        self.check_status_and_reason(response, 301)
+        self.assertEqual(response.getheader('Location'), self.tempdir_name + '/#foo')
+        response = self.request(self.tempdir_name + '/test%3Ffoo')
+        self.check_status_and_reason(response, 200, data=self.data)
+        response = self.request(self.tempdir_name + '/test%3Ffoo?foo')
+        self.check_status_and_reason(response, 200, data=self.data)
 
     def test_head(self):
         response = self.request(