  We analyze an adaptive finite element/boundary element procedure for scalar
elastoplastic interface problems involving friction, where a nonlinear
uniformly monotone operator such as the p-Laplacian is coupled to the linear
Laplace equation on the exterior domain. The problem is reduced to a
boundary/domain variational inequality, a discretized saddle point formulation
of which is then solved using the Uzawa algorithm and adaptive mesh refinements
based on a gradient recovery scheme. The Galerkin approximations are shown to
converge to the unique solution of the variational problem in a suitable
product of L^p- and L^2-Sobolev spaces.
