From the installation log of marble master: -- Installing: /local/kde4/lib/libmarblewidget.so.0.13.0 -- Installing: /local/kde4/lib/libmarblewidget.so.13 -- Installing: /local/kde4/lib/libmarblewidget.so The first file should actually be "libmarblewidget.so.13.0.0", or the second should be "libmarblewidget.so.0".
Not a bug.