within /usr/qt/3/ there should be symlink from /usr/qt/3/libqt.so to /usr/qt/3/libqt-mt.so I tried merging doxygen with qt3, and doxygen had -lqt in it's build script. This symlink should probably be added for compatibility for many other programs.
Well, I guess these symlinks can't hurt. Since anything trying to link against libqt.so.3 atm would be broken anyway. So I've added them to qt-3.0.3.1 (the qt-copy-3.0.3 distributed with kde3), committing now -> soon on rsync.