I'm glad to announce that I just finished building the first powersave and kpowersave packages for Fedora Core 4.
In order to get them working properly, you need to have dbus > 0.50 and hal > 0.5.4. Both can be installed from http://gnome-power.sourceforge.net/data/utopia.repo .
Unfortunatelly, I was only able to build powersave-0.11.2 because of missing cpufreq-utils 0.4 package on Fedora Core 4.
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