  We present XMM-Newton observations of three X-ray under-luminous elliptical
galaxies, NGC 3585, NGC 4494 and NGC 5322. All three galaxies have relatively
large optical luminosities (log LB=10.35-10.67 solar) but have X-ray
luminosities consistent with emission from discrete sources only. In
conjunction with a Chandra observation of NGC 3585, we analyse the XMM data and
show that the three galaxies are dominated by discrete source emission, but do
possess some X-ray emitting gas. The gas is at relatively low temperatures,
kT=0.25-0.44 keV. All three galaxies show evidence of recent dynamical
disturbance and formation through mergers, including kinematically distinct
cores, young stellar ages, and embedded stellar disks. This leads us to
conclude that the galaxies formed relatively recently and have yet to build up
large X-ray halos. They are likely to be in a developmental phase where the
X-ray gas has a very low density, making it undetectable outside the galaxy
core. However, if the gas is a product of stellar mass loss, as seems most
probable, we would expect to observe supersolar metal abundances. While
abundance is not well constrained by the data, we find best fit abundances <0.1
solar for single-temperature models, and it seems unlikely that we could
underestimate the metallicity by such a large factor.
