Please describe the problem:
We have a TreeView instance inside a ScrolledWindow.
Under certain conditions, the contents of the Scrolled Window seem to disappear,
and the scrollbar,although present contains no slider.

This behaviour can be found in both custom applications and those
shipped with gnome (on ubuntu at least).

Steps to reproduce:
1. Open Gthumb Viewer (/usr/bin/gthumb on breezy)
2. In the folder hierachy (which I believe is in a scrolled window), select the
root (/) folder.
3. Resize the main window such that only the first 5 folders are visible.
4. Without resizing the window, scroll to the /usr folder and select it.
5. Now the contents of the /usr folder appear empty, and the scrollbar's slider
   indicates that there are now entries. However, resizing the window will
display the contents of the folder - but only if you resize past the point where
all folders *would* be visible.


Actual results:
As described above.

Expected results:
As described above.

Does this happen every time?
Yes.

Other information:
We are using Python 2.4, python-gtk2, libgtk2.0-0 from the ubuntu (breezy
badger) linux platform.