  It is shown that in (2+1)-dimensional condensed matter systems, induced
gravitational Chern-Simons (CS) action can play a crucial role for coherent
spin transport in a finite geometry, provided zero-curvature condition is
satisfied on the boundary. The role of the resultant KdV solitons is
explicated. The fact that KdV solitons can pass through each other without
interference, represent 'resistanceless' spin transport.
