When testing at home on a Windows 7 VM, noticed that the latest download is now QT 4.6, so I've installed that locally too. Note that you still have to manually switch the QT version in the preferences screen, otherwise your apps will presumably be compiled and running against the old version. Also found a problem with the install; in order to use QOpenGL, you need to install libglui-dev, but this won't install on my Jaunty machine because it depends on freeglut-dev, which is not available. I'm not worrying about this right now, because I'm likely to move to Lucid Lynx by May. The app compiled and ran just fine, and I found and fixed another little bug.