  At energies higher than the brane tension, the dynamics of a scalar field
rolling down a potential are modified relative to the predictions of General
Relativity. The modifications imply, among other things, that steeper
potentials can be used to drive an epoch of slow--roll inflation. We
investigate the evolution of entropy and adiabatic modes during inflation
driven by two scalar fields confined on the brane. We show that the amount of
entropy perturbations produced during inflation is suppressed compared to the
predictions made by General Relativity. As a consequence, the initial
conditions do not matter in multiple field inflation in brane worlds if
inflation is driven at energies much higher than the brane tension.
