  Recent Monte Carlo simulation studies of a Lennard-Jones fluid confined to a
mesoscopic slit-pore have reported evidence for ``critical depletion'' in the
pore local number density near the liquid-vapour critical point. In this note
we demonstrate that the observed depletion effect is in fact a simulation
artifact arising from small systematic errors associated with the use of long
range corrections for the potential truncation. Owing to the large
near-critical compressibility, these errors lead to significant changes in the
pore local number density. We suggest ways of avoiding similar problems in
future studies of confined fluids.
