  We consider charge-symmetry violations in the nucleon-nucleon force which
result from isospin-violating meson-baryon coupling constants. The vector
mesons are assumed to couple to the nucleon's electromagnetic current, which we
decompose into isoscalar and isovector quark components. We compute these
currents in the context of a constituent quark model. The isospin violations in
the meson-baryon couplings arise from the difference in the up and down
constituent quark masses. We show that class IV charge-symmetry-breaking
potentials arise in the resulting $\omega$ and $\rho$ exchange contributions to
the $NN$ force. The magnitude of these contributions is consistent with that
phenomenologically required by the measured difference of $n$ and $p$ analyzing
powers in elastic $\vec{n}-\vec{p}$ scattering at 183 MeV.
