  The development of micropixel gas detectors, capable to image tracks produced
in a gas by photoelectrons, makes possible to perform polarimetry of X-ray
celestial sources in the focus of grazing incidence X-ray telescopes. HXMT is a
mission by the Chinese Space Agency aimed to survey the Hard X-ray Sky with
Phoswich detectors, by exploitation of the direct demodulation technique. Since
a fraction of the HXMT time will be spent on dedicated pointing of particular
sources, it could host, with moderate additional resources a pair of X-ray
telescopes, each with a photoelectric X-ray polarimeter in the focal plane. We
present the design of the telescopes and the focal plane instrumentation and
discuss the performance of this instrument to detect the degree and angle of
linear polarization of some representative sources. Notwithstanding the limited
resources the proposed instrument can represent a breakthrough in X-ray
Polarimetry.
