  The lack of regularity of geometric variables at the origin is often a source
of serious problem for spherically symmetric evolution codes in numerical
relativity. One usually deals with this by restricting the gauge and solving
the hamiltonian constraint for the metric. Here we present a generic algorithm
for dealing with the regularization of the origin that can be used directly on
the evolution equations and that allows very general gauge choices. Our
approach is similar in spirit to the one introduced by Arbona and Bona for the
particular case of the Bona-Masso formulation. However, our algorithm is more
general and can be used with a wide variety of evolution systems.
