  The Chandra observations of several gravitationally lensed quasars show
evidence for flux and spectral variability of the X-ray emission that is
uncorrelated between images and is thought to result from the microlensing by
stars in the lensing galaxy. We report here on the most detailed modeling of
such systems to date, including simulations of the emission of the Fe K-alpha
fluorescent radiation from the accretion disk with a general relativistic ray
tracing code, the use of realistic microlensing magnification maps derived from
inverse ray shooting calculations, and the simulation of the line detection
biases. We use lensing and black hole parameters appropriate for the quadruply
lensed quasar RX J1131-1231, and compare the simulated results with the
observational results. The simulations cannot fully reproduce the distribution
of the detected line energies indicating that some of the assumptions
underlying the simulations are not correct, or that the simulations are missing
some important physics. We conclude by discussing several possible
explanations.
