  Higgs Yukawa couplings to down-type fermions receive, in the MSSM,
supersymmetric quantum corrections that can be of order 1 for large values of
tan\beta, provided \mu \sim MSUSY. Therefore, a sensitive prediction for
observables driven by any of these couplings can only be obtained after an
all-order resummation of the large corrections. We perform this necessary step
and show, as an example, the effect of the resummation on the computation of
the p\bar{p},pp \to t\bar{b}H^{-} + X cross-section and on the branching ratio
BR(b\to s\gamma) at the next-to-leading order.
