By using very general and well established features of soft strong
interactions we show, contrary to conventional expectations, that (i) soft
final state interactions (FSI) do not disappear for large mB, (ii) inelastic
rescattering is expected to be the main source of soft FSI phases, and (iii)
flavor off-diagonal FSI are suppressed by a power of mB, but are quite
likely to be significant at mB≃5~GeV. We briefly discuss the influence
of these interactions on tests of CP-violation and on theoretical calculations
of weak decays.Comment: 11 pages, REVTeX, no figure