Sample-to-sample fluctuations of the Josephson current in superconduct
or-dirty normal metal-superconductor junctions are studied numerically
using a tight-binding model. Particular attention is given to the cas
es where the correlation energy of the normal metal is smaller than th
e superconducting pair potential. It is found that the amplitude of th
e critical-current fluctuation is of order of the correlation energy.
This result is in qualitative agreement with the theory of Al'tshuler
and Spivak.