  The Kubo formula is used to calculate the spin-Hall conductivity in a
spin-polarized two-dimensional electron system with Rashba-type spin-orbit
interaction. As in the case of the unpolarized electron system, spin Hall
conductivity is entirely determined by states at the Fermi level, a property
that persists in the presence of magnetic impurities. In the clean limit, the
spin-Hall conductivity decreases monotonically with the Zeeman splitting, a
result of the ordering effect on the electron spins produced by the magnetic
field. In the presence of magnetic impurities, the spin-dependent scattering
determines a finite renormalization of the static part of the fully dressed
vertex correction of the velocity operator that leads to an enhancement of the
\sigma_{sH}, an opposite behaviour to that registered in the presence of
spin-independent disorder. The variation of \sigma_{sH} with the strength of
the Rashba coupling and the Zeeman splitting is studied.
