  Temperature dependence of electron dephasing time $\tau_\phi(T)$ is
calculated for a disordered metal with small concentration of superconductive
grains. Above the macroscopic superconducting transition line, when electrons
in the metal are normal, Andreev reflection from the grains leads to a nearly
temperature-independent contribution to the dephasing rate. In a broad
temperature range $1/\tau_phi(T)$ strongly exceeds the prediction of the
classical theory of dephasing in normal disordered conductors, whereas
magnetoresistance is dominated (in two dimensions) by the Maki-Tompson
correction and is positive.
