  We show that conductance of 1D channel with one point-like impurity
critically depends on asymptotic behavior of e-e interaction at small momenta k
(about inverse length of a channel). Conductance reemerges (contrary to the
case of point-like repulsive potential) if potential V(k=0)= 0. For example,
this happens if the bare e-e interaction is screened by the charges in the
bulk. The relation of this phenomena to the long-range order present in the
Luttinger model is discussed.
