  We present a survey of X-ray point sources in a 91 ksec Chandra ACIS-S
observation of the z=0.83 cluster MS1054-0321. We detect 47 X-ray sources
within the 8.3 arcmin by 8.3 arcmin field, of which two are immediately
confirmed from pre-existing spectroscopy to be at the redshift of the cluster.
At fluxes brighter than S_(0.5 - 8 keV) = 5 x 10^{-15} erg s^{-1} cm^{-2} we
find a ~ 2 sigma excess compared to predictions from field surveys, consistent
with an excess of approximately 6 AGN. If these sources are associated with the
cluster, they too are AGN with luminosities of order L_(0.5 - 8 keV) ~ 10^{43}
erg s^{-1}. Combined with the identification of 7 cluster AGN from deep radio
observations (Best et al. 2002), these observations suggest significantly
enhanced AGN activity in MS1054-03 compared to local galaxy clusters.
Interestingly, the excess of X-ray detected AGN is found at radial distances of
between 1 and 2 Mpc, suggesting they may be associated with infalling galaxies.
The radio AGN are seen within the inner Mpc of the cluster and are largely
undetected in the X-ray, suggesting they are either intrinsically less luminous
and/or heavily obscured.
