  We propose a new model for impurity center formed by a cathion substitute for
Cu, like Zn, in CuO_{2} planes. Its main effect on superconducting electrons is
due to the non-zero exchange field on O sites, neighbors to the (non-magnetic)
impurity. We discuss a strong suppression of d-wave order parameter, a zero-
energy resonance in local density of states, and spin polarization of charge
carriers, which can be related to the experimentally observed effects in
Zn-doped copper oxides. These results are obtained \emph{without} using the
unitary scattering limit.
