How can I make one contour line created by geom\_contour a separate color than the others? For example, in the below code how can I keep all contour lines black except the one labeled 0.02, which I'd like to be a color other than used by the rest.

```
require(directlabels)
p <- ggplot(faithfuld, aes(eruptions, waiting)) + 
     geom_contour(aes(z = density, colour = ..level..))
p <- direct.label(p, list("bottom.pieces", cex = .6))

```