R help - May 2011 - 3D plot with it's quadratic approximation superimposed in same plot

Dear all, I would like to draw a 3D plot as shown
here?http://en.wikipedia.org/wiki/File:NaturalLogarithmAll.png, for this
function "f = exp[ 1 - x^2 - y^2]" (this function is some arbitrary!).
I am aware of different 3D plotting system in R, however it would be great if I
can get that kind of "soft look" (this will help me to make a
good-looking presentation.)

Additionally, I want to superimpose the Quadratic approximation (at some
arbitrary point) of that function, on the top of the same plot. Can somebody
help me to?achieve?that?

Thanks,