the masked version of cups is missing /etc/init.d/cupsd. I caught this on a new installation, as using the /etc/init.d/cupsd file that came with cups-1.1.23-r7 worked fine. It looks like simply adding the line newinitd ${FILESDIR}/cupsd.rc6 cupsd to the cups-1.2.1.ebuild will fix this problem.
yeah, I already fixed this, next reinstall will go fine for you :)