The feasibility of using the detection of electron antineutrinos produced in fission to monitor the time dependence of the plutonium content of nuclear power reactors is of interest to the IAEA. This possibility exists because the nuclear physics leads to a large difference in the neutrino spectra of Pu versus U. For GWe power reactors the count rates and the sensitivity of the antineutrino spectrum (to the core burn-up) suggest that monitoring of the gross operational status of the reactor from outside the containment vessel is feasible. However, it would be very difficult to detect the expected change in the antineutrino signal from the diversion of a significant quantity of plutonium (which would typically require the diversion of as little as a single fuel assemblies in a GWe reactor). Detailed analysis are hindered by uncertainties in many nuclide decay spectra of interest. We point out the need for better modeling of the high energy (E>6 MeV) component of fission spectra both for monitoring the Pu content of reactor cores and for reactor neutrino oscillation searches.