Description of problem: In my install.log from a fresh FC5T3 install: Installing avahi-0.6.6-3.1.i386. Installing avahi-0.6.6-3.1.x86_64. error: %post(avahi-0.6.6-3.1.x86_64) scriptlet failed, exit status 127 This is because initscripts (and /sbin/service) and chkconfig are not installed at this point. You need a: Requires(post): initscripts, chkconfig, ldconfig in your spec.
Now fixed with avahi-0.6.8-1 .