  Through the study of two absorption spectral features in the optical range
(Mg2 and the 4000 A break), we find evidence for star formation in the inner
regions of cooling-flow galaxies. The application of simple stellar population
models reveals that the measured indices are explained if a relatively small
fraction of the total mass flow (5-17%) is forming new stars with a normal IMF.
However, we argue that this is only a lower limit, and conclude that a large
fraction of the gas accreted inside the galaxy could be forming stars. In
addition, the analysis of line-strength gradients in the inner galaxy regions
reveals that, in the mean, they are lower than those of normal ellipticals, and
exhibit a hint of correlation with the mass accretion rate. Simultaneously, the
spectral indices in the outer regions of some galaxies, with and without
cooling flow, attain extremely low values, suggesting that they could be
hosting star formation with an origin not related to the cooling flows.
