the current john version in fedora doesn't support the current hash used in fedora so imho it'd be needed to update to the latest john release.
Thank you for the report, I will update john soon. But I doubt it will support the Fedora crypt hashes. I suppose you will need the jumbo patch for it: http://www.openwall.com/john/contrib/john-1.7.6-jumbo-7.diff.gz
john-1.7.6-1.fc13 has been submitted as an update for Fedora 13. http://admin.fedoraproject.org/updates/john-1.7.6-1.fc13
john-1.7.6-1.fc12 has been submitted as an update for Fedora 12. http://admin.fedoraproject.org/updates/john-1.7.6-1.fc12
john-1.7.6-1.fc14 has been submitted as an update for Fedora 14. http://admin.fedoraproject.org/updates/john-1.7.6-1.fc14
john-1.7.6-1.fc12 has been pushed to the Fedora 12 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 john'. You can provide feedback for this update here: http://admin.fedoraproject.org/updates/john-1.7.6-1.fc12
john-1.7.6-1.fc14 has been pushed to the Fedora 14 stable repository. If problems still persist, please make note of it in this bug report.
john-1.7.6-1.fc13 has been pushed to the Fedora 13 stable repository. If problems still persist, please make note of it in this bug report.