Fedora 18 changes the way how to work with services in spec files. It introduces new macros - %systemd_post, %systemd_preun and %systemd_postun; which replace scriptlets from Fedora 17 and older (see https://fedoraproject.org/wiki/Packaging:ScriptletSnippets#Systemd, https://bugzilla.redhat.com/show_bug.cgi?id=850016).
I just orphaned mod_pubcookie, since it won't build against apache 2.4, upstream has been dead for over a year, and my employer is moving away from it (in favor of shibboleth). Given that, I believe it's safe to assume mod_pubcookie won't be around in f18, and therefore dealing with its systemd-related issues would be redundant...