  This paper is devoted to numerical simulations of the magnetization dynamics
driven by a spin-polarized current in extended ferromagnetic multilayers when a
point-contact setup is used. We present (i) detailed analysis of methodological
problems arising by such simulations and (ii) physical results obtained on a
system similar to that studied in Rippard et al., Phys. Rev. Lett., v. 92,
027201 (2004). We demonstrate that the usage of a standard Slonczewski
formalism for the phenomenological treatment of a spin-induced torque leads to
a qualitative disagreement between simulation results and experimental
observations and discuss possible reasons for this discrepancy.
