One question is whether this is a bug fix or a feature request.
Other than that, I'd like to see the test classes collapsed into a single test class, considering that each one only has a single test in it. Probably ProxyAuthTests should be refactored so that the stuff that is currently in setUp is a method that gets called with appropriate parameters instead, and all the new tests moved on to ProxyAuthTests.
Also, a version of the patch for 3.x would be most helpful, since it won't port cleanly due to the renamings.