  We investigate the existence and the singular structure of delta wave
solutions to a semilinear strictly hyperbolic equation with strongly singular
initial and boundary conditions. The boundary conditions are given in nonlocal
form with a linear integral operator involved. We construct a delta wave
solution as a distributional limit of solutions to the regularized system. This
determines the macroscopic behavior of the corresponding generalized solution
in the Colombeau algebra $\G$ of generalized functions. We represent our delta
wave as a sum of a purely singular part satisfying a linear system and a
regular part satisfying a nonlinear system.
