  We consider the minimal 3-3-1 model with a heavy scalar sextet and realize,
at the tree level, an effective dimension-five interaction that contributes to
the mass of the charged leptons. In this case the charged leptons masses arise
from a sort of type-II seesawlike mechanism while the neutrino masses are
generated by a type-I mechanism. We also show that the parameters giving the
correct lepton masses also accommodate the Pontecorvo-Maki-Nakawaga-Sakata
matrix. We give the scalar mass spectra of the model and analyze under which
conditions the fields in the scalar sextet are heavy even with small or zero
vacuum expectation values. We also show the conditions under which it is
possible to have a stable (bounded from below) potential and also a global
minimum.
