A smaller trove of photos of mainly Tommies, but which also includes some Australians, was reported in The Independent in 2009, taken in late 1915 and early 1916.
See also the Australian War Memorial blog with an article by Peter Burness.
UPDATE: And there is a Facebook page - thanks to Linda for the link.
ANOTHER UPDATE: The above links now do not appear to show the whole set of photos, so see the report on the Lost Diggers from the AWM here. As at December 2011 these photos do not appear to have been added to the AWM online catalogue.