set_usize of hbox/vbox

["Riswick, J.G.A. van" <J G A v Riswick tue nl>]

HI

in my application I have a hbox and I pack vboxes into it, 
which each contain 2 drawing areas. Now I'd like the vboxes
to have the same size, except for the 2 at the outer edges
of the hbox, those I'd like to make narrower. I tried using
set_usize on the vboxes, but somehow this doesn't seem to 
give a predictable result. The vboxes that I set to a narrower
width, do appear narrower, but they don't take the exact width
given in set_usize. I did make shure that te drawingareas that
I put into the vboxes have the correct size. Is there some way
of setting the width/height of a widget explicitly, without
compromises?

best regards

jos