  We demonstrate that the zero-temperature conductance of the Anderson model
can be calculated within the Landauer formalism combined with static density
functional theory (DFT). The proposed approximate functional is based on
finite-temperature DFT and yields the exact Kohn-Sham potential at the
particle-hole symmetric point. Furthermore, in the limit of zero temperature it
correctly exhibits a derivative discontinuity which is shown to be essential to
reproduce the conductance plateau. On the other hand, at the Kondo temperature
the exact Kohn-Sham conductance overestimates the real one by an order of
magnitude. To understand the failure of DFT we resort to its time-dependent
version and conclude that the suppression of the Kondo resonance with
increasing temperature must be attibuted to dynamical exchange-correlation
corrections.
