Index: Doc/library/urllib2.rst
===================================================================
--- Doc/library/urllib2.rst	(revision 65357)
+++ Doc/library/urllib2.rst	(working copy)
@@ -318,13 +318,15 @@
 
 .. method:: Request.add_header(key, val)
 
-   Add another header to the request.  Headers are currently ignored by all
-   handlers except HTTP handlers, where they are added to the list of headers sent
-   to the server.  Note that there cannot be more than one header with the same
-   name, and later calls will overwrite previous calls in case the *key* collides.
-   Currently, this is no loss of HTTP functionality, since all headers which have
-   meaning when used more than once have a (header-specific) way of gaining the
-   same functionality using only one header.
+   Add another header to the request. This method adds the key in .capitalize()
+   format, but when headers are passed to HTTP Handlers, they are internally
+   coverted the required .title() format. Headers are currently ignored by all
+   handlers except HTTP handlers, where they are added to the list of headers
+   sent to the server.  Note that there cannot be more than one header with the
+   same name, and later calls will overwrite previous calls in case the *key*
+   collides.  Currently, this is no loss of HTTP functionality, since all
+   headers which have meaning when used more than once have a (header-specific)
+   way of gaining the same functionality using only one header.
 
 
 .. method:: Request.add_unredirected_header(key, header)
@@ -337,7 +339,7 @@
 .. method:: Request.has_header(header)
 
    Return whether the instance has the named header (checks both regular and
-   unredirected).
+   unredirected and in a case-insensitive manner.
 
    .. versionadded:: 2.4
 
Index: Lib/urllib2.py
===================================================================
--- Lib/urllib2.py	(revision 65357)
+++ Lib/urllib2.py	(working copy)
@@ -182,6 +182,38 @@
     host = _cut_port_re.sub("", host, 1)
     return host.lower()
 
+class CaseInsensitiveDict(dict):
+    def __init__(self, *args, **kwargs):
+        self.keystore = {}
+        d = dict(*args, **kwargs)
+        for k in d.keys():
+            self.keystore[self._get_lower(k)] = k
+        return super(CaseInsensitiveDict, self).__init__(*args, **kwargs)
+    def __setitem__(self, k, v):
+        if hasattr(self,'keystore'):
+            self.keystore[self._get_lower(k)] = k
+        return super(CaseInsensitiveDict, self).__setitem__(k, v)
+    def __getitem__(self, k):
+        if hasattr(self,'keystore') and self._get_lower(k) in self.keystore:
+            k = self.keystore[self._get_lower(k)]
+        return super(CaseInsensitiveDict, self).__getitem__(k)
+    def __contains__(self, k):
+        if hasattr(self,'keystore') and self._get_lower(k) in self.keystore:
+            k = self.keystore[self._get_lower(k)]
+        return super(CaseInsensitiveDict, self).__contains__(k)
+    def get(self, k, failobj=None):
+        if hasattr(self,'keystore') and self._get_lower(k) in self.keystore:
+            k = self.keystore[self._get_lower(k)]
+        return super(CaseInsensitiveDict, self).get(k, failobj)
+
+    @staticmethod
+    def _get_lower(k):
+        if isinstance(k, str):
+            return k.lower()
+        else:
+            return k
+
+
 class Request:
 
     def __init__(self, url, data=None, headers={},
@@ -193,10 +225,12 @@
         self.host = None
         self.port = None
         self.data = data
-        self.headers = {}
+        #self.headers = {}
+        self.headers = CaseInsensitiveDict()
         for key, value in headers.items():
             self.add_header(key, value)
-        self.unredirected_hdrs = {}
+        #self.unredirected_hdrs = {}
+        self.unredirected_hdrs = CaseInsensitiveDict()
         if origin_req_host is None:
             origin_req_host = request_host(self)
         self.origin_req_host = origin_req_host
Index: Lib/test/test_urllib2.py
===================================================================
--- Lib/test/test_urllib2.py	(revision 65357)
+++ Lib/test/test_urllib2.py	(working copy)
@@ -53,7 +53,9 @@
     stay that way, because the complete set of headers are only accessible
     through the .get_header(), .has_header(), .header_items() interface.
     However, .headers pre-dates those methods, and so real code will be using
-    the dictionary.
+    the dictionary. .get_header() and .has_header() and .headers support case-
+    insensitive dict lookup for header keys. .header_items() returns them in
+    .capitalize() form.
 
     The introduction in 2.4 of those methods was a mistake for the same reason:
     code that previously saw all (urllib2 user)-provided headers in .headers
@@ -63,7 +65,6 @@
     interface and also provided access to the "unredirected" headers.  It's
     probably too late to fix that, though.
 
-
     Check .capitalize() case normalization:
 
     >>> url = "http://example.com"
@@ -72,9 +73,14 @@
     >>> Request(url, headers={"spam-EggS": "blah"}).headers["Spam-eggs"]
     'blah'
 
-    Currently, Request(url, "Spam-eggs").headers["Spam-Eggs"] raises KeyError,
-    but that could be changed in future.
+    Check case-insensitive dict lookup.
 
+    >>> Request(url, headers={"spam-EggS": "blah"}).headers["Spam-Eggs"]
+    'blah'
+    >>> Request(url, headers={"spam-EggS": "blah"}).headers["spam-eggs"]
+    'blah'
+    >>> Request(url, headers={"spam-EggS": "blah"}).headers["SPAM-EGGS"]
+    'blah'
     """
 
 def test_request_headers_methods():
@@ -82,12 +88,19 @@
     Note the case normalization of header names here, to .capitalize()-case.
     This should be preserved for backwards-compatibility.  (In the HTTP case,
     normalization to .title()-case is done by urllib2 before sending headers to
-    httplib).
+    httplib). .has_header and .get_header support case-insensitive lookup to
+    support cases where headers are retrived (mostly) through .title() form.
 
     >>> url = "http://example.com"
     >>> r = Request(url, headers={"Spam-eggs": "blah"})
     >>> r.has_header("Spam-eggs")
     True
+    >>> r.has_header("Spam-Eggs")
+    True
+    >>> r.has_header("spam-eggs")
+    True
+    >>> r.has_header("spaM-EggS")
+    True
     >>> r.header_items()
     [('Spam-eggs', 'blah')]
     >>> r.add_header("Foo-Bar", "baz")
@@ -96,9 +109,13 @@
     >>> items
     [('Foo-bar', 'baz'), ('Spam-eggs', 'blah')]
 
-    Note that e.g. r.has_header("spam-EggS") is currently False, and
-    r.get_header("spam-EggS") returns None, but that could be changed in
-    future.
+    >>> req = urllib2.Request(url)
+    >>> req.add_header("spam-eggs", "eggs")
+    >>> req.add_header("SPAM-eggs", "ham") # Later headers will be over-written
+    >>> req.header_items()
+    [('Spam-eggs', 'ham')]
+    >>> req.headers.items()
+    [('Spam-eggs', 'ham')]
 
     >>> r.has_header("Not-there")
     False