The paper reports on a study of the resolution of the proper-time of the B0 and B+ mesons. The decay modes used are B+ --> J/psi(mu+mu-) K+ and B0 --> J/psi(mu+mu-) K*(K+pi-) and their conjugates. A resolution model based on the proper-time residuals and the corresponding per-event error is proposed and results are presented on the two decay modes studied. While the model still requires further refinement the approach presented appears promising
