In the meantime, a workaround is to edit /usr/share/i18n/locales/en_AU to adjust date_fmt appropriately, and then run
localedef -f UTF-8 -i en_AU en_AU.UTF-8
as root.
Without root, the procedure is (something like) take a copy of
/usr/share/i18n/locales/en_AU, edit it, run
localedef -f UTF-8 -i ./en_AU ~/locales/en_AU.UTF-8
and then set $LOCPATH to ~/locales.
Kev
