  Screening of a macroion by multivalent counterions is considered. It is shown
that ions form strongly correlated liquid at the macroion surface. Cohesive
energy of this liquid leads to strong additional attraction of counterions to
the surface. Away from the surface this attraction is taken into account by a
new boundary condition for the Poisson-Boltzmann equation. This equation is
solved with the new boundary condition for a charged flat surface and a long
cylinder. For a cylinder Onsager-Manning theory looses its universality so that
apparent charge of the cylinder is smaller than their theory predicts and
depends on its bare charge. It can also vanish or change sign.
