In this paper we calculate the O(alpha(s)) corrections to the x(F) and
y distributions of lepton pairs produced in collisions of longitudina
lly polarized hadrons. The numerical importance of these corrections i
s studied and consequences for the extraction of the polarized sea-qua
rk distributions from a measurement of the longitudinally polarized Dr
ell-Yan cross section are discussed. (C) 1997 Elsevier Science B.V.