Description of problem: chkconfig --add should not be conditional on the number of packages installed. Version-Release number of selected component (if applicable): 0.6.9-6
Now fixed with avahi-0.6.9-8.FC5
avahi-0.6.9-6 has been pushed for FC5, which should resolve this issue. If these problems are still present in this version, then please make note of it in this bug report.
I think this can be closed now.