  We report on a peculiar X-ray binary pulsar IKT1 = RXJ0047.3-7312 observed
with XMM-Newton in Oct. 2000. The X-ray spectrum is described by a
two-component spectrum. The hard component has a broken power-law with
respective photon indices of 0.2 and 1.8, below and above the break energy at
5.8 keV. The soft component can be modeled by a blackbody of kT = 0.6 keV. The
X-ray flux shows a gradual decrease and periodic variations of about 4000 s.
The averaged flux in 0.7-10.0 keV is 2.9x10^-12 ergs/cm^2/s, which is ~10 times
brighter than that in a ROSAT observation in Nov. 1999. In addition to the
4000-s variation, we found coherent pulsations of 263 +/- 1 s. These
discoveries strengthen the Be/X-ray binary scenario proposed by the ROSAT and
ASCA observations on this source, and confirm that most of the hard sources in
the Small Magellanic Cloud are X-ray binary pulsars. A peculiar property of
this XBP is that the coherent pulsations are found only in the soft component,
and the folded light curve shows a flat top shape with a sharp dip. We discuss
the nature of this XBP focusing on the peculiar soft component.
