  The role of the strange quark mass for the phase structure of QCD at
non-vanishing densities is studied by employing a recently developed
self-consistent truncation scheme for the Dyson-Schwinger equations of the
quark propagators in Landau gauge. Hereby the medium modification of the
effective quark interaction by the polarization of gluons is implemented.
Taking into account this effect results in significantly smaller dynamical
quark masses at the Fermi surface. Due to this reduction the color-flavor
locked phase is always the preferred color-superconducting phase at zero
temperature and for a realistic strange quark mass.
