Invoke HTTPConnection or M2Crypto's HTTPSConnection directly, instead, and
process everything through xmlrpclib's utility functions on the way in and
out by hand.

(Note that we can't use native Python's HTTPSConnection, or native
xmlrpclib with an HTTPS URL for that matter, because Python's SSL
support does not handle custom callbacks to retrieve passphrases,
which we want to do.  We can't override that behaviour with Python
code, since it lives in a binary shared library.)