I suggest modify the ebuilds. Add "paxctl -cm /usr/games/bin/openarena" (No aspa) to pkg_postinst() in the present and future ebuilds.
what problem is this suggestion trying to solve?
After taking to the hardened team I'm marking this bug as WONTFIX since apparently only some video cards needs the pax marking and it's expected that if you're using a hardened system that you'll know what you're doing enough to do any necessary marking yourself.