  We consider modified $t-J$ model with minimum of single-hole dispersion at
the points $(0,\pm \pi)$, $(\pm \pi,0)$. It is shown that two holes on
antiferromagnetic background produce a bound state which properties strongly
differs from the states known in the unmodified $t-J$ model. The bound state is
d-wave, it has four nodes on the face of the magnetic Brillouin zone. However,
in the coordinate representation it looks like as usual s-wave.
