  The main properties of the interaction of ultra low-energy antiprotons ($%
E\le10^{-6}$ a.u.) with atomic hydrogen are established. They include the
elastic and inelastic cross sections and Protonium (Pn) formation spectrum. The
inverse Auger process ($Pn+e \to H+\bar{p}$) is taken into account in the
framework of an unitary coupled-channels model. The annihilation cross-section
is found to be several times smaller than the predictions made by the black
sphere absorption models. A family of $\bar{p}H$ nearthreshold metastable
states is predicited. The dependence of Protonium formation probability on the
position of such nearthreshold S-matrix singularities is analysed. An
estimation for the $H\bar{H}$ annihilation cross section is obtained.
