Problem when applying Patch from issue1424152 to get https over authenticating proxies working with urllib2 in Python 2.5

[tvashtar]

Hi,
I'm trying to get https requests working through an authenticating
proxy with urllib2 in Python 2.5, I'm aware that this isn't supported
"out of the box", so applied the patch http://bugs.python.org/file9753/http-tunnel-urllib
linked from http://bugs.python.org/issue1424152 , my baseline test
program is the following:

p = "user:pass at proxy:port"
proxy_handler = urllib2.ProxyHandler({"http": p, "https": p})
urllib2.install_opener( urllib2.build_opener( urllib2.HTTPHandler,
 
urllib2.HTTPSHandler,
 
proxy_handler))

request = urllib2.Request( "https://groups.google.com")
response = urllib2.urlopen(request)

Unfortunately this doesn't work, the call stack being:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 121, in urlopen
    return _opener.open(url, data)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 374, in open
    response = self._open(req, data)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 392, in _open
    '_open', req)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 353, in _call_chain
    result = func(*args)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 1108, in https_open
    return self.do_open(httplib.HTTPSConnection, req)
  File "D:\p4\depot\Development\HEAD\Build\ReleaseSystem\DownloadSystem
\urllib2.py", line 1075, in do_open
    raise URLError(err)
urllib2.URLError: <urlopen error (1, 'error:140770FC:SSL
routines:SSL23_GET_SERVER_HELLO:unknown protocol')>

Does anyone know why I might be hitting this issue?
Any help is greatly appreciated,
thanks