"Unpublished" in publication series display

A book with the "unpublished" date of 8888-00-00 should appear in a Publication Series display as "Unpublished", and not with the "8888-00-00" publication date. An example is the <a href="http://www.isfdb.org/cgi-bin/pubseries.cgi?137">Bibliographies of Modern Authors</a> series. This is particularly difficult to see when a series like that is listed in "Sort by series number" order.