"Skinny" scrollbars

[sml13 cornell edu]

In playing around with the Mac Look-and-Feel (trying to get it more 
true-to-life...although, I must say Zaphod did a mighty fine job), I 
was wondering if there was any way to get the scrollbars to be "fatter."  
Right now they don't really look like bona fide Mac scrollbars because 
they are too skinny, more like your Motif scrollbars:

http://24.3.242.128/981119182230.jpg
http://24.3.242.128/981119183033.jpg

This raises a broader question:  Is the SIZE and SHAPE of a widget 
"themeable?"  I 
can see how this would be problematic for a developer who didn't know 
what size his widgets were going to be "themed" to (if the final app was 
themeable by a user), but I also think it would be "cool" to make the 
"emulator" themes look as accurate as possible.  I know you can achieve a 
kind of pseudo-size/shape-themability with transparent pixmaps, but that 
isn't really the same thing (it's kind of a hack).  

The Win95 rendering 
engine  suffers from this same "skinny scrollbar" problem.  
Is it easier (or even possible) to set the size of standard widgets when 
you do your own engine?  I know Java Swing's PLAF 
(pluggable-look-and-feel)--which uses a sort of rendering-engine 
architecture--allows you to customize this.  Is such a feature slated for 
GTK+?  Or should I just shut my mouth and start coding it myself (like I 
could!:-). 

just curious,

shane