diff -r 52fbc7bb78ad Lib/test/test_wsgiref.py
--- a/Lib/test/test_wsgiref.py	Sat Jan 11 00:16:50 2014 +0100
+++ b/Lib/test/test_wsgiref.py	Sat Jan 11 11:42:06 2014 +0200
@@ -286,7 +286,7 @@
     def testAppURIs(self):
         self.checkAppURI("http://127.0.0.1/")
         self.checkAppURI("http://127.0.0.1/spam", SCRIPT_NAME="/spam")
-        self.checkAppURI("http://127.0.0.1/sp%C3%A4m", SCRIPT_NAME="/späm")
+        self.checkAppURI("http://127.0.0.1/sp%E4m", SCRIPT_NAME="/späm")
         self.checkAppURI("http://spam.example.com:2071/",
             HTTP_HOST="spam.example.com:2071", SERVER_PORT="2071")
         self.checkAppURI("http://spam.example.com/",
@@ -300,15 +300,19 @@
     def testReqURIs(self):
         self.checkReqURI("http://127.0.0.1/")
         self.checkReqURI("http://127.0.0.1/spam", SCRIPT_NAME="/spam")
-        self.checkReqURI("http://127.0.0.1/sp%C3%A4m", SCRIPT_NAME="/späm")
+        self.checkReqURI("http://127.0.0.1/sp%E4m", SCRIPT_NAME="/späm")
         self.checkReqURI("http://127.0.0.1/spammity/spam",
             SCRIPT_NAME="/spammity", PATH_INFO="/spam")
+        self.checkReqURI("http://127.0.0.1/spammity/sp%E4m",
+            SCRIPT_NAME="/spammity", PATH_INFO="/späm")
         self.checkReqURI("http://127.0.0.1/spammity/spam;ham",
             SCRIPT_NAME="/spammity", PATH_INFO="/spam;ham")
         self.checkReqURI("http://127.0.0.1/spammity/spam;cookie=1234,5678",
             SCRIPT_NAME="/spammity", PATH_INFO="/spam;cookie=1234,5678")
         self.checkReqURI("http://127.0.0.1/spammity/spam?say=ni",
             SCRIPT_NAME="/spammity", PATH_INFO="/spam",QUERY_STRING="say=ni")
+        self.checkReqURI("http://127.0.0.1/spammity/spam?s%E4y=ni",
+            SCRIPT_NAME="/spammity", PATH_INFO="/spam",QUERY_STRING="s%E4y=ni")
         self.checkReqURI("http://127.0.0.1/spammity/spam", 0,
             SCRIPT_NAME="/spammity", PATH_INFO="/spam",QUERY_STRING="say=ni")
 
diff -r 52fbc7bb78ad Lib/wsgiref/util.py
--- a/Lib/wsgiref/util.py	Sat Jan 11 00:16:50 2014 +0100
+++ b/Lib/wsgiref/util.py	Sat Jan 11 11:42:06 2014 +0200
@@ -57,14 +57,14 @@
             if environ['SERVER_PORT'] != '80':
                 url += ':' + environ['SERVER_PORT']
 
-    url += quote(environ.get('SCRIPT_NAME') or '/')
+    url += quote(environ.get('SCRIPT_NAME') or '/', encoding='latin1')
     return url
 
 def request_uri(environ, include_query=True):
     """Return the full request URI, optionally including the query string"""
     url = application_uri(environ)
     from urllib.parse import quote
-    path_info = quote(environ.get('PATH_INFO',''),safe='/;=,')
+    path_info = quote(environ.get('PATH_INFO',''), safe='/;=,', encoding='latin1')
     if not environ.get('SCRIPT_NAME'):
         url += path_info[1:]
     else: