new to gtk, how can I limit widgets?

[ian baber <ian jabberwock botworks com>]

I'm working on a project using the GTK2 perl package, and I need a  
way to set absolute limits on a container widget.  The program needs  
to be able to divide up the screen using several containers, and then  
hand each of those off to a plugin.  The problem is that I want the  
containers to ALWAYS remain the same size, regardless of how much or  
how little the plugin puts in it.  If the children widgets won't fit,  
they should be truncated/cut off at the edge.

Is there a way to do this in GTK?