The reason why qmake doesn't run when you type just 'qmake' is because with 4.6 it is installed in /opt/qt4-maemo5/bin/qmake which is not in PATH environment variable. So you can either add the folder /opt/qt4-maemo5/bin/ to your PATH, or always type '/opt/qt4-maemo5/bin/qmake' instead of 'qmake', or make symbolic link 'ln -s /opt/qt4-maemo5/bin/qmake /usr/bin/qmake' so you can just type 'qmake'.