  The one-particle three-dimensional Dirac equation with spherical symmetry is
solved for the Hulthen potential. The s-wave relativistic energy spectrum and
two-component spinor wavefunctions are obtained analytically. Conforming to the
standard feature of the relativistic problem, the solution space splits into
two distinct subspaces depending on the sign of a fundamental parameter in the
problem. Unique and interesting properties of the energy spectrum are pointed
out and illustrated graphically for several values of the physical parameters.
The square integrable two-component wavefunctions are written in terms of the
Jacobi polynomials. The nonrelativistic limit reproduces the well-known
nonrelativistic energy spectrum and results in Schrodinger equation with a
"generalized" three-parameter Hulthen potential, which is the sum of the
original Hulthen potential and its square.
