There are currently several configuration files throughout the source code repository that contain configuration variables, e.g. etc/default/openattic, debian/default/openattic and rpm/sysconfig/openattic.*.
The one in etc/default seems to be unused, so it should be removed. The ones in rpm/sysconfig currently only contain the Nagios-specific settings, so they should be extended to include all other settings currently provided by etc/default/openattic or which are created "on the fly" by the RPM spec file rpm/openattic.spec.
Any script or tool that makes use of these config values should be updated to handle both locations (/etc/default/openattic and /etc/sysconfig/openattic), to support both Debian-based and RPM-based distributions.