  We discuss the possibility of generating noncritical quadrature squeezing by
spontaneous polarization symmetry breaking. We consider first type-II
frequency-degenerate optical parametric oscillators, but discard them for a
number of reasons. Then we propose a four-wave mixing cavity in which the
polarization of the output mode is always linear but has an arbitrary
orientation. We show that in such a cavity complete noise suppression in a
quadrature of the output field occurs, irrespective of the parameter values.
