diff --git a/Lib/Cookie.py b/Lib/Cookie.py
index b4f9db4e820..323450b38ab 100644
--- a/Lib/Cookie.py
+++ b/Lib/Cookie.py
@@ -258,6 +258,11 @@ _Translator       = {
     '\033' : '\\033',  '\034' : '\\034',  '\035' : '\\035',
     '\036' : '\\036',  '\037' : '\\037',
 
+    # Because of the way browsers really handle cookies (as opposed
+    # to what the RFC says) we also encode , and ;
+
+    ',' : '\\054', ';' : '\\073',
+
     '"' : '\\"',       '\\' : '\\\\',
 
     '\177' : '\\177',  '\200' : '\\200',  '\201' : '\\201',
diff --git a/Lib/test/test_cookie.py b/Lib/test/test_cookie.py
index 0e74ccf6a4f..d09398dca1f 100644
--- a/Lib/test/test_cookie.py
+++ b/Lib/test/test_cookie.py
@@ -72,6 +72,14 @@ class CookieTests(unittest.TestCase):
         self.assertEqual(C['Customer']['expires'],
                          'Wed, 01-Jan-98 00:00:00 GMT')
 
+    def test_extended_encode(self):
+        # Issue 9824: some browsers don't follow the standard; we now
+        # encode , and ; to keep them from tripping up.
+        C = Cookie.SimpleCookie()
+        C['val'] = "some,funky;stuff"
+        self.assertEqual(C.output(['val']),
+            'Set-Cookie: val="some\\054funky\\073stuff"')
+
     def test_quoted_meta(self):
         # Try cookie with quoted meta-data
         C = Cookie.SimpleCookie()
diff --git a/Misc/NEWS b/Misc/NEWS
index 809148cf39f..6ffb39a1dcd 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -22,6 +22,9 @@ Core and Builtins
 Library
 -------
 
+- Issue 9824: SimpleCookie now encodes , and ; in values to cater to how
+  browsers actually parse cookies.
+
 - Issue #1379416: eliminated a source of accidental unicode promotion in
   email.header.Header.encode.