  The possibilities to determine the flavor structure of the polarized sea
(antiquark) distributions of the nucleon via vector boson $(\gamma^*, W^{\pm},
Z^0)$ production at high energy polarized hadron--hadron colliders, such as the
Relativistic Heavy--Ion Collider (RHIC), are studied in detail. In particular
the perturbative stability of the expected asymmetries in two representative
models for the (un)broken flavor structure are investigated by confronting
perturbative QCD leading order predictions of the expected asymmetries with
their next--to--leading order counterparts.
