This is because of new faulty qt4.4 from hardy backports. Use synaptic, remove all qt, libqt, libqtcore and everything else qt (lyx, skype and stellarium will follow). Then remove hardy-backports from the sources and resync. Then install libqt4-core and libqt4-gui at version 4.3. Then lyx and everythong else. Now everything should be fine.
This is because of new faulty qt4.4 from hardy backports. Use synaptic, remove all qt, libqt, libqtcore and everything else qt (lyx, skype and stellarium will follow). Then remove hardy-backports from the sources and resync. Then install libqt4-core and libqt4-gui at version 4.3. Then lyx and everythong else. Now everything should be fine.