cfdg 3.0-0.beta2.fc18 is not built with $RPM_OPT_FLAGS: http://kojipkgs.fedoraproject.org/packages/cfdg/3.0/0.beta2.fc18/data/logs/x86_64/build.log Additionally, the default flags appear to include -O3 and -march=native which means the resulting binaries quite probably won't work on all target systems.
Bizarre, I updated the patch for optflags to the new version, and for some reason wasn't applying it. Thanks, good catch, fixed.