This should go upstream: https://code.launchpad.net/~markmc/nova/flat-dhcp-without-bridge-iface
openstack-nova-2011.3-1.fc16 has been submitted as an update for Fedora 16. https://admin.fedoraproject.org/updates/openstack-nova-2011.3-1.fc16
Package openstack-nova-2011.3-1.fc16: * should fix your issue, * was pushed to the Fedora 16 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing openstack-nova-2011.3-1.fc16' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/openstack-nova-2011.3-1.fc16 then log in and leave karma (feedback).
openstack-nova-2011.3-3.fc16 has been submitted as an update for Fedora 16. https://admin.fedoraproject.org/updates/openstack-nova-2011.3-3.fc16
openstack-nova-2011.3-3.fc16 has been pushed to the Fedora 16 stable repository. If problems still persist, please make note of it in this bug report.