Description of problem: the name of explicit mapping file generated by SSSD in /var/lib/sss/pubconf/krb5.include.d/ contains non-filtered domain name, which contains dot. krb5.conf manual page states that includedir statement allows to source all files which names are constructed from alpha-numeric chars, dashes and underscores. Files with other characters are ignored. So dots as in domain_realm_example.com are ignored and our mapping is never sourced. This prevents explicit mapping for trusted domains in FreeIPA to not work.
Upstream ticket: https://fedorahosted.org/sssd/ticket/1795
sssd-1.9.4-4.fc18 has been submitted as an update for Fedora 18. https://admin.fedoraproject.org/updates/sssd-1.9.4-4.fc18
Package sssd-1.9.4-4.fc18: * should fix your issue, * was pushed to the Fedora 18 testing repository, * should be available at your local mirror within two days. Update it with: # su -c 'yum update --enablerepo=updates-testing sssd-1.9.4-4.fc18' as soon as you are able to. Please go to the following url: https://admin.fedoraproject.org/updates/FEDORA-2013-2637/sssd-1.9.4-4.fc18 then log in and leave karma (feedback).
sssd-1.9.4-5.fc18 has been submitted as an update for Fedora 18. https://admin.fedoraproject.org/updates/sssd-1.9.4-5.fc18
sssd-1.9.4-5.fc18 has been pushed to the Fedora 18 stable repository. If problems still persist, please make note of it in this bug report.