The -f should not be necessary. gtk-update-icon-cache compares the mtimes of the cache file and the directory it is in to determine if the cache is outdated. Maybe the redhat-artwork %post forgets to touch the directory. Matthias
When not using the -f flag it seems to me, that if the cache file already is "up2date", or rather "ok", it doesnt get an updated time-stamp, even if the directory is older than the cache-file. Possible scenario: A new redhat-artwork rpm is released which contains a small fix, resulting in that fixing the cache is unneccesary. The directories timestamp is increased, so the icon-cache gets outdated, the %post script runs but since the small fix didn't require a rebuild of the cache, and because of this "possible" bug, it's left as is.