sWidth and nested tables

greenflash

Is sWidth obeyed absolutely, or is it tempered by some other data? I'm trying to build a datatable where you can expand a row using fnOpen() and reveal a subtable, which I am also turning into a datatable. The subtable has the same number of columns as the main table and I want the columns to align. I don't know in advance how wide the columns should be. I thought I could achieve this by using jQuery to get the widths of the main table columns before the expansion and then applying those values as sWidths to the subtable. However it does not seem to work - the subtables are off by +/- a few pixels.

Any ideas?

Campbell