[BioC] spatial correlation and design question

[Simon Melov]

Hi,
I am trying to estimate the spatial correlation for a series of arrays. 
My design encompasses 9 separate groups (4-5 technical reps per group), 
and each array has each gene spotted 4 times. When I estimate the 
spatial correlation as per the guide, I only get one number.  Given 
that I have 9 distinct groups as defined by my design, shouldnt I get 9 
separate correlations for use in the gls.series function?

thanks

Simon.