Changing standard error color for geom_smooth

I'm plotting some data using geom_smooth and looking for a way to change the color of the standard error shading for each line to match that line (ie., a red line would have it's standard error shaded red). I've looked through the official ggplot2 documentation as well as the list of opts() at https://github.com/hadley/ggplot2/wiki/%2Bopts%28%29-List. Any advice (or just confirmation of whether or not it's possible) is appreciated.