How to get window decoration sizes?

Hi,

There has been a bug for some time relating to wnck set_geometry() not
placing windows as specified.  (See my post in June
"wnck.window.set_geometry() misbehaving" and gnome bug 518606).

Alas, this bug still remains, and so as a work-around, I need to
determine the width/height of the decorations surrounding a window.  I
am new to python and GTK, and it is not clear to me how to make a query
for these sizes.

I'm including my code below that illustrates how the new geometry
differs from the requested geometry.

Thanks for any tips,

Jason.

==========================

The following little program prints:

Requested: 1, 50, 550, 250
New      : 4, 71, 548, 246

==========================

pygtk.require('2.0')
import gtk
import gobject