We investigate a new numerical procedure to compute fermionic correlation
functions at very small quark masses. Large statistical fluctuations, due to
the presence of local ``bumps'' in the wave functions associated with the
low-lying eigenmodes of the Dirac operator, are reduced by an exact low-mode
averaging. To demonstrate the feasibility of the technique, we compute the
two-point correlator of the left-handed vector current with Neuberger fermions
in the quenched approximation, for lattices with a linear extent of L~1.5 fm, a
lattice spacing a~0.09 fm, and quark masses down to the epsilon-regime. By
matching the results with the corresponding (quenched) chiral perturbation
theory expressions, an estimate of (quenched) low-energy constants can be
obtained. We find agreement between the quenched values of F extrapolated from
the p-regime and extracted in the epsilon-regime.Comment: 20 pages, 5 figure