locfit and geom_smooth

locfit shows SEs instead of CIs when used with stat_smooth.

```r
library(locfit)
library(ggplot2)

data(ethanol)

# 99% CIs computed by locfit
fit = locfit(NOx~E, data=ethanol)
crit(fit) = crit(fit, cov=0.99)
plot(fit, band="local")

# 99% CIs displayed by ggplot
qplot(E, NOx, data=ethanol) + 
  stat_smooth(method="locfit", level=0.99)
```
