  We argue that the $d_{x^2-y^2}$-wave superconductor is marginally stable in
the presence of external perturbations. Subjected to the external perturbations
by magnetic impurities, it develops a secondary component of the gap, complex
$d_{xy}$, to maximize the coupling to impurities and lower the total energy.
The secondary $d_{xy}$ component exists at high temperatures and produces the
full gap $\sim 20 K$ in the single particle spectrum around each impurity,
apart from impurity induced broadening. At low temperatures the phase ordering
transition into global $ d_{x^2-y^2} + i d_{xy}$ state occurs.
