Reccomendation for graphics package

It should be trivial with ggplot2 too, but it's hard to provide
concrete advice without a concrete problem.

Elementary problem:

qplot(wg, v.realtime, data=df.best.medians$gv1, facets = . ~ n, colour=sp)

produces a nice plot. Adding a geom="line" produces everything *except* the
lines that show the dataset!  What am I doing wrong? (R-2.9.0, on 64-bit Vista;
package freshly installed from CRAN)

By the way, how can I rotate axis labels by 90 degrees (they are rather
long and they overlap when placed without rotation).