  In this talk, we shall assess the finite ma errors from the overlap fermion.
We shall present results on the speed of light from the dispersion relation and
hyperfine splitting between the vector and pseudoscalar mesons as a function to
ma to reveal the m\Lambda_{QCD}a^2 and m^2a^2 errors. We conclude from this
study that one should be limited to using ma less than 0.5 in order to keep the
systematic ma errors below a few percent level.
