jhrozek's pull request #15: "Avoid returning System Error on clock skew" was
Rather return ERR_NETWORK_IO and at least let the user authenticate offline.
See the full pull-request at https://github.com/SSSD/sssd/pull/15
... or pull the PR as Git branch:
git remote add ghsssd https://github.com/SSSD/sssd
git fetch ghsssd pull/15/head:pr15
git checkout pr15