R help - Jun 2006 - plotting grouped data with nlme over several pages

Hi
I am struggling to split up the plots of the grouped objects in nlme in a 
usable way. The standard plot command generates plots for each group on a 
single page. When there are many groups however this does not look so good. 
I have discovered the layout option which allows one to split up these plots 
over a certain number of pages but the problem is it very quickly scrolls 
through all the pages only leaving the final page in the viewer.

My question is how does one get to view all these pages? or even better is 
there an option where the pages change only when prompted by the user?

Thanks

Greg