  We obtain accurate resonance energies for the Schr\"{o}dinger equation with a
central--field potential by means of a method based on a rational approximation
to the logarithmic derivative of the wavefunction. We discuss the rate of
convergence of our approach and compare present results with those obtained
earlier by other authors. We show that present method is superior to the
spherical--box approach applied recently to the same problem. As far as we know
present results are more accurate than those available in the literature and
may be a suitable benchmark for testing future approaches.
