R help - Apr 2006 - variable labels in pairs

Hello,

I am using 'pairs' to produce a scatter plot matrix with a custom
upper.panel function to plot the Pearson's correlation coefficients for the
pairs of variables.  

I would like to be able to use the actual variable names as subscripts in
rho in the printed text.  I know these labels are accessible to diag.panel
but cannot find a good way to access them within panel.cor.

Any suggestions?

Thank you.
-Christos  

### --- code snip -----------

panel.cor <-
function(x, y, digits=3, subscripts, groups, cex.cor=2) {
    usr <- par("usr"); on.exit(par(usr))
    par(usr = c(0, 1, 0, 1))
    r <- abs(cor(x, y))
    txt <- format(c(r, 0.123456789), digits=digits)[1]
    txt <- substitute(italic(rho) == txt)
    text(0.5, 0.5, txt, cex = cex.cor, col="blue")
}
pairs(my.df, upper.panel=panel.cor)