branching from Launchpad behind a proxy

[Tim Michelsen]

Dear Bazaar & Launchpad developers,
I and numerous other users find it very hard to 
branch repositories from Launchpad (LP) when being 
behind a proxy firewall.

Here is a summary of related reports:

bzr xmlrpc client doesn't use http proxy, causing network errors trying to
resolve lp: urls
https://bugs.launchpad.net/python/+bug/186920

Error while using "bzr branch" through proxy
https://bugs.launchpad.net/bzr/+bug/83954

no able to branch from launchpad behind proxy (squid)
https://bugs.launchpad.net/bzr/+bug/509543

how to branch from launchpad behind squid?
https://answers.launchpad.net/bzr/+question/60728

I know that for at least one project previously hosted 
on LP this drawback was a reason to move over to 
Mercurial at google code.

For comparison, in TortoiseSVN, I just edit the 
corresponding setting and it works.
For Mercurial I could use a global setting or run
hg --config http_proxy.host=proxy.example.com:8000 clone http://hg.example.com/repo
which works with bitbucket, their major hosting site
using http and not https.

So if there is something obvious that I and others are 
overlooking here, please point us to the 
documentation.

Thanks in advance for your help,