Comment 4 for bug 194097

Ok, I'm far away from being a network and proxy expert, but my first guess is you need to use an https proxy, since launchpad is using https for all requests. Can you please try this:
$ export https_proxy=http://<host>:<port>
$ bugnumbers -p bughelper

and check the output (I think this will return an exception as py-lp-bugs really is not supporting proxies, but this should not be a 'connection refused' error)

Markus