Description of problem:
Icons from iconized applications do not appear in Gnome Window
List when iconized on a dual head display, when they were originally
displayed on the "other head", i.e. the screen other than the
one the panel is on.  The window selector does keep track of
them however.

Version-Release number of selected component (if applicable):
FC3 only, I believe things were fine back in FC1

How reproducible:
I see this every time on my two dual head systems (both use
the Nvidia driver, if that is relevant).

Steps to Reproduce:
1. Run an X session with a panel on the rightmost of
two screens in a dual head setup.
2. Bring up a terminal in the right screen, iconize it and
it will properly appear in the window list.
3. Bring up a terminal in the left screen, iconize it and
for all intensive purposes it is gone and you wonder how to
get it back again (run a Window Selector as a workaround).