Possible to vary widths and/or heights of lattice panels?

Is it possible to vary the size of the panels in lattice within one 
page?  The examine I have in mind is a 3 row by 2 column display where I 
vary the y-axis scales in a dot plot and there are only a few levels on 
the y-axis for one of the rows.  I'd like to remove wasted space in that 
row.

On a related issue 
http://stackoverflow.com/questions/9654244/multipage-lattice-panel-arrangement 
has some good information.

Thanks for any pointers.
Frank