I have squid installed on my system but currently (recently) disabled. The weekly logrotate reports, "squid: ERROR: No running copy". It should not make any noise if squid is not running.
squid-3.0.STABLE18-3.fc11 has been submitted as an update for Fedora 11. http://admin.fedoraproject.org/updates/squid-3.0.STABLE18-3.fc11
squid-3.0.STABLE18-3.fc11 has been pushed to the Fedora 11 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 squid'. You can provide feedback for this update here: http://admin.fedoraproject.org/updates/F11/FEDORA-2009-9410
squid-3.0.STABLE18-3.fc11 has been pushed to the Fedora 11 stable repository. If problems still persist, please make note of it in this bug report.