  We adapt the results of Part 1 to include the unit ball in the Heisenberg
group, the model domain with characteristic boundary points. In particular, we
construct function spaces on which the Kohn Laplacian with the
\bar{\partial}_b-Neumann boundary conditions is an isomorphism. As an
application, we establish sharp regularity for a canonical solution to the
inhomogenous \bar{\partial}_b equation on the unit ball.
