Adding category "with children" checked fails

When issuing grants to any role, I am unable to use the "with children" option. When I select a root, or any parent, in the hierarchy and click add I receive the following error:

PDOException: SQLSTATE[23000]: Integrity constraint violation: 1062 Duplicate entry '1-4' for key 'PRIMARY': INSERT INTO {taxonomy_access_term} (tid, rid, grant_view, grant_update, grant_delete, grant_create, grant_list) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_1, :db_insert_placeholder_2, :db_insert_placeholder_3, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6); Array ( [:db_insert_placeholder_0] => 1 [:db_insert_placeholder_1] => 4 [:db_insert_placeholder_2] => 0 [:db_insert_placeholder_3] => 0 [:db_insert_placeholder_4] => 0 [:db_insert_placeholder_5] => 0 [:db_insert_placeholder_6] => 0 ) in drupal_write_record() (line 6868 of /var/www/drupal-7.8/includes/common.inc).

When I go back to the grants page, the parent that was selected HAS been added but the children have not.