Comments on `Rashba precession in quantum wire with interaction'

In a recent Rapid Communication (Phys. Rev. B {\bf 63}, 121210(R) (2001)), Ha\"usler showed that the interaction between electrons in quantum wires may enhance the persistent spin current arising from Rashba spin-orbital coupling. In this Comments, we would like to point out that this 'enhancement' comes from a misunderstanding to the boosting persistent current in the Luttinger liquid theory. A correct calculation will not give such an enhancement of the persistent spin current. Meanwhile, we provide a Luttinger liquid theory with Rashba spin-orbital interaction by bosonization, which may show how the Rashba precession is in a Luttinger liquid.