indicator simple kriging with varying local mean on gstat

Dear guys,

I want to use the indicator simple kriging with varying local mean on gstat.

Do you have a script example about it?

I do not understand which is the local mean that I have to put in the command 
of simple indicator kriging.....

 I do not also well understand whether if it is posssible to use the 
semivariogram model in SK, because theory tells that it need the covariance 
function.......

Any suggest?

Thank you.

Cristiano