There also is a clash with the dev packages: Package: libsmf-dev,denemo Version: libsmf-dev/1.3-1 Version: denemo/0.8.10-1 Unpacking libsmf-dev (from .../libsmf-dev_1.3-1_amd64.deb) ... dpkg: error processing /var/cache/apt/archives/libsmf-dev_1.3-1_amd64.deb (--unpack): trying to overwrite '/usr/include/smf.h', which is also in package denemo 0:0.8.10-1 -Ralf.