  We discuss contributions of the KK modes to the crossover length scale
$r_{\rm c}$ for the brane-induced force when the brane is given by a solitonic
background field. We work in a 5D scalar model with a domain-wall background
that mimics the DGP model. In spite of the infinite number of the KK modes, the
crossover scale remains finite due to the warping effect on the ambient space
of the domain wall. The inclusion of the KK modes relaxes the hierarchy among
the model parameters that is required to realize a phenomenologically viable
size of $r_{\rm c}$. We also discuss whether a nontrivial dilaton background
enlarges $r_{\rm c}$ or not.
