  We reconsider the possible presence of charge and colour breaking minima in
the scalar potential of the minimal supersymmetric standard model (MSSM) and
its minimal generalization with R-parity explicitly broken by bilinear terms
(RMSSM). First we generalize some results previously derived for the MSSM case.
Next we investigate how robust is the MSSM against its RMSSM extension. We
examine the constraints on the RMSSM parameter space that follow from the
required absence of charge breaking minima in the scalar potential. We point
out the possibility of generating non--zero vacuum expectation values for the
charged Higgs field which is not present in the MSSM. However, given the
smallness of neutrino masses indicated by neutrino oscillation data, we show
that the RMSSM represents only a slight perturbation of the MSSM and is thus as
safe (or unsafe) as the MSSM itself from unwanted minima in the scalar
potential.
