How can I plot this graph

...
What I need is the following

- One graph 
- y1, y2, y3 plotted as seperate lines vs x
- z1, z2 give the range of the value of z, and need to be plotted as error bars or confidence intervals vs x

This doesn't look right to me, but it might give you a start:

library(plotrix)
brkdn.plot(c("y1","y2","y3"),NA,"x",xxx,
  dispbar=FALSE,col=2:4,ylim=c(-3,10))
dispbars(xxx$x,xxx$y1,xxx$z1,col=2)
dispbars(xxx$x-0.12,xxx$y2,xxx$z2,col=3)

Jim