Comment 14 for bug 254278

Reproduced this with a mod_wsgi + http smart server setup using a single daemon group for multiple vhosts.
Ubuntu Lucid Lynx, standard apt versions of bazaar (2.1.1) and mod_wsgi.

As mentioned in comment #9, it's the monkeypatched performance improving bits of xml_serializer which cause this to break - removing them fixes this issue.

I applied the following changes directly to xml_serializer.
https://code.edge.launchpad.net/~gz/bzr/remove_monkey_patched_elementtree_escaping_614522/+merge/34028