Currently setcifsacl just returns an error if it can't load the plugin. It should instead allow a user to supply a "raw" SID string in that case. getcifsacl will already print them, so it's just a matter of accepting them in reverse.
cifs-utils-6.1-3.fc19 has been submitted as an update for Fedora 19. https://admin.fedoraproject.org/updates/cifs-utils-6.1-3.fc19
Package cifs-utils-6.1-3.fc19: * should fix your issue, * was pushed to the Fedora 19 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing cifs-utils-6.1-3.fc19' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2013-13079/cifs-utils-6.1-3.fc19 then log in and leave karma (feedback).
cifs-utils-6.1-3.fc19 has been pushed to the Fedora 19 stable repository. If problems still persist, please make note of it in this bug report.