Relationship-editor shows "The end date cannot preceed the begin date" incorrectly

For example if I try to modify composer relationship on this to have 1741-9-29 as start date and 1741-10-29 as end date I get "The end date cannot preceed the begin date": http://beta.musicbrainz.org/work/d9990fe5-f40b-4226-b10f-ac090cc79440/edit