Luminescence from dilute magnetic semiconductors (DMSs) such as Cd0.95Mn0.05S, in which the magnetic ion Mn2+ randomly replaces the host cation, has been studied. The spectroscopic behavior of Cd0.95Mn0.05S is reported to change markedly when the particles are aged in micellar solution. It is concluded that the high luminescence efficiency observed for Mn2+-doped nanocrystals cannot be attributed to a particle-size effect, as expected within the framework of an electron-hole localization theory. Instead, the luminescence is attributed to the aging and/or passivation of the particles.