  Corrections to the semiclassical approximation in nearly forward Planckian
energy collisions are here reconsidered. Starting from the one-loop superstring
amplitude, we are able to disentangle the first subleading high-energy
contribution at large impact parameters, and we thus directly compute the
one-loop correction to the superstring eikonal. We finally argue, on the basis
of analyticity and unitarity, that gravitinos do not contribute at all to the
large distance two-loop ACV correction, which thus acquires a universal
``classical'' interpretation.
