  The standard definition of a spin current, applied to the conductors lacking
inversion symmetry, results in nonzero spin currents. I demonstrate that the
spin currents do not vanish even in the thermodynamic equilibrium, in the
absence of external fields. These currents are dissipationless and are not
associated with a real spin transport. The result should be taken as a warning
indicating problems inherent in the theory of transport spin currents driven by
external fields.
