  We present molecular dynamics simulations of the motion of a single rod in a
two-dimensional random static array of disks. For long rods the mean-squared
displacement of the center-of-mass shows a cage effect similar to that observed
in supercooled liquids or dense colloidal systems. We have determined the
time-dependence of the non-Gaussian parameter for different rod lengths. It is
found that the long-time regime is strongly non-Gaussian even at length scales
of the order of 10-15 times the rod length, thus showing the heterogeneity of
the dynamics at such length scales.
