  Using an exact expression for the domain wall tension in a supersymmetric
model we show that a spectrum crossover takes place in passing from weak to
strong coupling. In the weak coupling regime elementary excitations are the
lightest states, while in the strong coupling regime solitonic objects of a
special type -- bubbles -- assume the role of the lightest states. The
crossover occurs at \lambda^2/(4\pi) \sim 0.4.
