You probably have something (directly or indirectly) depending on 'python2.5-qt4'
Nokia-N810-23-14:~# apt-get install libqt4-gui Reading package lists... Done Building dependency tree Reading state information... Done The following extra packages will be installed: libqt4-assistant libqt4-dbus libqt4-designer libqt4-network libqt4-script libqt4-svg libqt4-xml libqtgui4 Recommended packages: qt4-qtconfig The following NEW packages will be installed: libqt4-assistant libqt4-dbus libqt4-designer libqt4-gui libqt4-network libqt4-script libqt4-svg libqt4-xml libqtgui4 0 upgraded, 9 newly installed, 0 to remove and 17 not upgraded. Need to get 8635kB of archives. After unpacking 25.1MB of additional disk space will be used. Do you want to continue [Y/n]?
Nokia-N810-23-14:~# apt-get install libqt4-core Reading package lists... Done Building dependency tree Reading state information... Done The following extra packages will be installed: libqt4-dbus libqt4-network libqt4-script libqt4-test libqt4-xml libqtgui4 Recommended packages: qt4-qtconfig The following NEW packages will be installed: libqt4-core libqt4-dbus libqt4-network libqt4-script libqt4-test libqt4-xml libqtgui4 0 upgraded, 7 newly installed, 0 to remove and 17 not upgraded. Need to get 5932kB of archives. After unpacking 15.9MB of additional disk space will be used. Do you want to continue [Y/n]?