Hi all,
  I've wrote a patch to fix this, it works fine for me with gnutls
support enabled, so I thought it may be useful.

PS: If without gnutls support, it needs to be modified to use external
program with https via proxy support(e.g. openssl s_client post-May 2015 release version:
http://rt.openssl.org/Ticket/Display.html?id=2651) other than just throw an
error. But I think very few people will need this since this bug report
stayed with outstanding status for such a long time.

Here is the patch: