Comment 17 for bug 1210253

The cloud archive does not yet have the fix. It's not terribly hard to patch the packages locally, though. Summary:

apt-get install build-essential
apt-get source horizon
apt-get build-dep horizon
cd horizon-*
# apply the changes to debian/rules and debian/changelog at
# http://launchpadlibrarian.net/148082203/horizon_1%3A2013.2~b2-0ubuntu2_1%3A2013.2~b2-0ubuntu3.diff.gz
# (although probably you will want a different version number, so
# the next ubuntu cloud archive version superceeds yours)
dpkg-buildpackage -us -uc
cd ..

install the resulting .debs with "dpkg -i", or put them in a ppa, or some other repo, etc.

I've confirmed that these changes fix at least the problem described here. I'm then having a different problem: when I log in, I get redirected back to the login page, with no error in the browser or apache's error.log that I can find. However, that is probably more likely something I did wrong upgrading from grizzly to havanah, or a separate issue.