Even with "Allow Dangerous Changes" and --force, pushing a branch closure commit to a hosted mercurial repository returns:
remote: [2014-05-14 10:35:51] ERROR 2: vsprintf(): Too few arguments at [/var/www/code.interworks.com/libphutil/src/internationalization/PhutilTranslator.php:93]
remote: #0 vsprintf(Mercurial repository has no new head for branch "%s" after push. This is unexpected; rejecting change., Array ) called at [/var/www/code.interworks.com/libphutil/src/internationalization/PhutilTranslator.php:93]
remote: #1 PhutilTranslator::translate(Mercurial repository has no new head for branch "%s" after push. This is unexpected; rejecting change.)
remote: #2 call_user_func_array(Array of size 2 starting with: { 0 => Object PhutilTranslator }, Array { 0 => Mercurial repository has no new head for branch "%s" after push. This is unexpected; rejecting change. }) called at [/var/www/code.interworks.com/libphutil/src/internationalization/pht.php:19]
remote: #3 pht(Mercurial repository has no new head for branch "%s" after push. This is unexpected; rejecting change.) called at [/var/www/code.interworks.com/phabricator/src/applications/diffusion/engine/DiffusionCommitHookEngine.php:735]
remote: #4 DiffusionCommitHookEngine::findMercurialChangegroupRefUpdates() called at [/var/www/code.interworks.com/phabricator/src/applications/diffusion/engine/DiffusionCommitHookEngine.php:656]
remote: #5 DiffusionCommitHookEngine::findMercurialRefUpdates() called at [/var/www/code.interworks.com/phabricator/src/applications/diffusion/engine/DiffusionCommitHookEngine.php:202]
remote: #6 DiffusionCommitHookEngine::findRefUpdates() called at [/var/www/code.interworks.com/phabricator/src/applications/diffusion/engine/DiffusionCommitHookEngine.php:124]
remote: #7 DiffusionCommitHookEngine::execute() called at [/var/www/code.interworks.com/phabricator/scripts/repository/commit_hook.php:104]
remote: [2014-05-14 10:35:51] EXCEPTION: (Exception) at [/var/www/code.interworks.com/phabricator/src/applications/diffusion/engine/DiffusionCommitHookEngine.php:732]
remote: #0 DiffusionCommitHookEngine::findMercurialChangegroupRefUpdates() called at [/var/www/code.interworks.com/phabricator/src/applications/diffusion/engine/DiffusionCommitHookEngine.php:656]
remote: #1 DiffusionCommitHookEngine::findMercurialRefUpdates() called at [/var/www/code.interworks.com/phabricator/src/applications/diffusion/engine/DiffusionCommitHookEngine.php:202]
remote: #2 DiffusionCommitHookEngine::findRefUpdates() called at [/var/www/code.interworks.com/phabricator/src/applications/diffusion/engine/DiffusionCommitHookEngine.php:124]
remote: #3 DiffusionCommitHookEngine::execute() called at [/var/www/code.interworks.com/phabricator/scripts/repository/commit_hook.php:104]
remote: transaction abort!
remote: rollback completed
remote: abort: pretxnchangegroup.phabricator hook exited with status 255