  We present Extended Double BRST on the lattice and extend the Neuberger
problem to include the ghost/anti-ghost symmetric formulation of the non-linear
covariant Curci-Ferrari (CF) gauges. We then show how a CF mass regulates the
0/0 indeterminate form of physical observables, as observed by Neuberger, and
discuss the gauge-parameter and mass dependence of the model.
