[R-sig-Geo] anisotropy - intamap

[seba]

Dear list members

I have a tecnical question in relation to the calculation of 
variogram anisotropy in presence of a trend with estimateParameters function.
I have a data set "w" with a clear trend (degree 1) so I would like 
to calculate geometric anisotropy of residuals.
I do the following:
  bingo=createIntamapObject(observations=w,formulaString=as.formula(z~x+y),params=getIntamapParams(),class="automap")
  estimateParameters(bingo,model=c("Pow"))->p

But when I go to check for anisotropy I have the impression that the 
anisotropy calculated is relative to the raw variogram not to the residual one:
Is it possible?
Is there something wrong in my expression?
Thank you in advance for your help.

Bye
Sebastiano