  The electron current tensor for the scattering of heavy photon on
longitudinally polarized electron accompanied with additional hard
electron-positron pair has been considered. The contribution of collinear and
semicollinear kinematics is computed. The full analysis of both, spin-dependent
and spin-independend parts of electron current tensor, is performed. The
obtained result allows to calculate the corresponding contribution into the
second order radiative correction to cross-sections of different processes with
the next-to-leading accuracy.
