Abstract: We shall describe a mechanism explaining recently observed spin conductance oscillations. A model in which the spin flip occurs at point impurities will be analyzed. It reproduces the experimental data - see P. Seba, P. Exner, K.N. Pichugin, A. Vyhnal, P. Streda: Two-component interference effect: model of a spin-polarized transport, Phys. Rev. Lett. 86 (2001), 1598-1601.