R help - Jan 2011 - Function rearrange (quantreg)

Dear all
   How can I obtain the data from the function "rearrange" in package
quantreg
   More especifically, based on the example below (available in the help of the
   rearrange function), how can I access the data generated by
   "rearrange(zp)" ?
   data(engel)
z <- rq(foodexp ~ income, tau = -1,data =engel)
zp <-
predict(z,newdata=list(income=quantile(engel$income,.03)),type="stepfun")
plot(zp,do.points = FALSE, xlab = expression(tau),
        ylab = expression(Q ( tau )), main="Engel Food Expenditure
Quantiles")
plot(rearrange(zp),do.points = FALSE,
add=TRUE,col.h="red",col.v="red")

   Thanks,
   Mauro