The munin package uses rrdtool-perl to generate it's graphs. In F8, the rrdtool-perl package seems to cause pango to spit out a bunch of warnings. Because munin-graph runs from a cron, it emails the admin user every 5 minutes with a list of pango warnings. See bug: 376441 for the orig munin report. Happy to provide more info to help track this down. It basically makes munin unusable due to all the pile of cron emails. ;(
Fixed in rrdtool 1.3.0-2.beta2, already built for rawhide, building shortly for F8. I'll push it to updates-testing asap.
rrdtool-1.3-0.2.beta2.fc8 has been pushed to the Fedora 8 testing repository. If problems still persist, please make note of it in this bug report. If you want to test the update, you can install it with su -c 'yum --enablerepo=updates-testing update rrdtool'
Appears to be resolved on f8 by the latest munin in updates-testing.