2 questions about likfit in geoR

Dear all,

I have two questions about using the likfit function in geoR.
One is about the trend estimation. The likfit function estimates the mean 
parameters and the covariance parameters at the same time. Is there any way 
to specify the trend function to be a fixed number? For example let mean be 
zero?

The second question is the function gives beta.var,  which is the estimated 
variance  for the mean
parameter beta. Can we also get the estimated variance for the covariance 
parameters kappa, sigma^2 and phi?

Thanks a lot!

Lauren Ma