Stacktrace is as follows:
> ./bin/repository parents CI Rebuilding "rCI"... Rebuilding branch "master"... Rebuilding branch "X"... Rebuilding branch "Y"... Rebuilding branch "Z"... Found 1,296 total commit(s); updating... [2014-05-27 23:09:52] EXCEPTION: (Exception) Unknown commit "a1d5645eabf502a8d830c5d52e1e9f1953939957"! at [/usr/src/phabricator/src/applications/repository/management/PhabricatorRepositoryManagementParentsWorkflow.php:114] #0 PhabricatorRepositoryManagementParentsWorkflow::rebuildRepository(Object PhabricatorRepository) called at [/usr/src/phabricator/src/applications/repository/management/PhabricatorRepositoryManagementParentsWorkflow.php:43] #1 PhabricatorRepositoryManagementParentsWorkflow::execute(Object PhutilArgumentParser) called at [/usr/src/libphutil/src/parser/argument/PhutilArgumentParser.php:396] #2 PhutilArgumentParser::parseWorkflowsFull(Array of size 14 starting with: { PhabricatorRepositoryManagementCacheWorkflow => Object PhabricatorRepositoryManagementCacheWorkflow }) called at [/usr/src/libphutil/src/parser/argument/PhutilArgumentParser.php:292] #3 PhutilArgumentParser::parseWorkflows(Array of size 14 starting with: { PhabricatorRepositoryManagementCacheWorkflow => Object PhabricatorRepositoryManagementCacheWorkflow }) called at [/usr/src/phabricator/scripts/repository/manage_repositories.php:22]