2. Have you tried "lmer" in library(lme4)? The syntax will be
different, but it's a different algorithm and can handle problems that
crash "lme". This may or may not apply to you. For documentation on
this, see Douglas Bates (2005) "Fitting linear mixed models in R. R
News, 5(1):27-30, available from www.r-project.org -> newsletter. See
also "Implementation.pdf" in the "doc" subdirectory under "lme4" in the
"library" folder of your R installation; if you are not using Windows,
I don't know if this is how you find this document.