  Recently D. A. R. Dalvit and S. K. Lamoreaux arXiv:0805.1676 [Phys. Rev.
Lett. v.101, 163203 (2008)] suggested the modification of the reflection
coefficients in the Lifshitz theory taking into account the screening effects
and diffusion currents. We demonstrate that the suggested modification is
thermodynamically and experimentally inconsistent.
