If possible, use debian testing or unstable.
To compile and run scribus without problem in Ubuntu 12.10 you may need to set the paths to python libs or add them to cmake command line, otherwise python3 libs will be preferred over python2
cmake ../Scribus -DWANT_SYSTEM_CAIRO=1 -DCMAKE_INSTALL_PREFIX=../Scribus-bin -DPYTHON_LIBRARY=/usr/lib/libpython2.7.so -DPYTHON_INCLUDE_DIR=/usr/include/python2.7