  The existence of millisecond pulsars with planet-mass companions (Bailes et
al., 2011) in close orbits is challenging from the stellar evolution point of
view. We calculate in detail the evolution of binary systems self-consistently,
including mass transfer, evaporation and irradiation of the donor by X-rays
feedback, demonstrating the existence of a new evolutionary path leading to
short periods and compact donors as required by the observations of PSR
J1719-1438. We also point out the alternative of an exotic nature of the
companion planet-mass star.
