I have a data frame created with this code:
require(reshape2)
foo <- data.frame( abs( cbind(rnorm(3),rnorm(3, mean=.8),rnorm(3, mean=.9),rnorm(3, mean=1))))
q
Try this:
ggplot(data=alldf.m, aes(x=variable, y = value, colour = ID, group = ID)) +
geom_line() + facet_wrap(~fn)

Even it is a ggplot2 is required by the OP , but I think this example is suitable for lattice also:
library(lattice)
xyplot(data=alldf.m, value~variable|fn, type ='b', groups = ID, auto.key = T)

and using latticeExtra we can get something colse to ggplot2 solution:
p <- xyplot(data=alldf.m, value~variable|fn, type ='b', groups = ID, auto.key = T)
update(p , par.settings = ggplot2like())
