lme in S-Plus 5

[Steve Ellis <ellis@neuron.cpmc.columbia.edu>]

I'm using S-Plus 5 for UNIX.  I wish to carry out a mixed model analysis
using lme.  Specifically, I wish to fit a model with one random effect
and a cluster covariance structure that I wish to write myself.  The
documentation on doing this sort of thing appears to be rather sketchy.
Can someone send me some examples similar to the sort of thing I wish to
do?  Thanks.

        -- Steve Ellis