http://gerrit.beaker-project.org/#/c/2123/
verified on beaker-devel(2013-7-28)-->pass Steps: 1.open user preferences page. 2.input non_existing_username in User box under the submission delegate list, such as '111'. 3. click button Add. Actual results: Then page contain '111 is not a valid user' and it cannot be added. Expected results: same with actual result.
Beaker 0.14.1 has been released.