I would like to add 95% confidence intervals to a median spline. It does not appear to be an option of mspline and the other confidence interval shading options seem to be determined by a regression plot

for example,

Code:
use http://www.stata-press.com/data/r13/auto, clear
tw (qfitci mpg weight, nofit fintensity(10)) (scatter mpg weight, msize(*.5)) (mspline mpg weight)
Is there a way to have the shading determined by the spline as opposed to the quadratic regression?