e+ e- pairs from pi- A reactions

We calculate dilepton production for the reactions $\pi^-$C and $\pi^-$Pb at 1.3 GeV within a semi-classical BUU transport model and compare our results to a previously published calculation. We show that a modified treatment of the $\rho$-meson production and propagation gives substantially different results. We, furthermore, discuss uncertainties related to the electromagnetic decay of the $\rho$-meson and the elementary $\pi^- N \to e^+ e^- X$ channels.