rainbow 0.8.5-1 is built without $RPM_OPT_FLAGS, thus creating a useless (no sources) debuginfo package and missing compiler security features: http://kojipkgs.fedoraproject.org/packages/rainbow/0.8.5/1.fc13/data/logs/x86_64/build.log [...for example...] cc -std=gnu99 -fPIC -W -Wformat -Wall -Wundef -Wpointer-arith -Wcast-qual -Wcast-align -Wwrite-strings -Wsign-compare -Wmissing-noreturn -Wextra -Wstrict-aliasing=2 -Wunsafe-loop-optimizations -MMD -MP -O3 -c -o nss-rainbow.o nss-rainbow.c See bug 496968 for more info.
Should be fixed in rainbow-0.8.5-2.f13; please close if satisfied or comment if further remediation is necessary.
0.8.5-2.f13 looks better.