[R-sig-Geo] spatial regression with generalized least squares

[G. Allegri]

I have a question about using GLS estimation within the Regression
Kriging framework.
In Rossiter and Hengl texts it is stated that it makes not so much
difference, in many practical situations, using OLS rather then GLS.
I'd like to test it in my work.
What's the more feasible way to adobt it in R?
The RK method suggests to use iteratively the regression coefficient
estimates using the covariance matrix derived from the residual
covariance modelling.

1 - How to automate this iteration scheme? I'm not so expert in R scripting...
2 - Could gls, from the nlme package, be used?

Giovanni