The Ebeling-Grigo (EG) improvement of the mean-spherical approximation (MSA) via the Bjerrum theory of ionic association in the restricted primitive model (RPM) is reviewed and extended. We find that, in terms of reduced density and temperature, the critical point (p(c)*, T-c*) of the EG approximation (EGA) is located at (0.026, 0.0789), rather than the (0.018, 0.0837) quoted by EG. The corrected result is closer to the most recent simulation estimates of the RPM critical point. A further improvement is obtained by incorporating the activity coefficient of the associated ionic pair to yield a dipole-ion (DI) contribution. The new approximation, EGA+DI, has a critical point at (0.027, 0.0716), which is in still better agreement with the simulation estimates. A critical discussion comparing these results with recent simulation results and other recent theoretical work is given.