  We consider a quantum dot coupled to two BCS superconductors with same gap
energies $\Delta$. The transport properties are investigated by means of
infinite-$U$ noncrossing approximation. In equilibrium density of states, Kondo
effect shows up as two sharp peaks around the gap bounds. Application of a
finite voltage bias leads these peaks to split, leaving suppressed peaks near
the edges of energy gap of each lead. The clearest signatures of the Kondo
effect in transport are three peaks in the nonlinear differential conductance:
one around zero bias, another two at biases $\pm 2\Delta$. This result is
consistent with recent experiment. We also predict that with decreasing
temperature, the differential conductances at biases $\pm 2\Delta$ anomalously
increase, while the linear conductance descends.
