KDE SC 4.4.2 packages in qt-kde.debian.net have been superseded by packages
uploaded to official Debian experimental archive and therefore they were
removed from the semi-official repository. As it was written on the
introductory page of qt-kde.debian.net, the repository itself will remain to
exist and might get some random extremely bleeding edge updates from time to
time. Feel free to keep it in your /etc/apt/sources.list.