How to retrieve the current desktop background

[Hans Oischinger <hans oischinger h3c de>]

Hi,

I'm the author of Kompose[1], a fullscreen taskmanager for KDE, quite similar 
to Apple's Expose but without the fancy zooming effects.
Kompose also works quite well on the Gnome desktop, there is however one 
quirk:
The routine I use to retrieve the current desktop background (a shared pixmap 
in KDE) does not work for Gnome.
Is there a way to do the same in gnome? And if yes: Is there also a way to get 
notified when the desktop background changes?

I hope to fix this long-standing bug as I often get requests from gnome users 
wanting to use Kompose as it seems to be the most comfortable (in UI terms) 
of all fullscreen takswitchers. Would be great to make them happy, too.

Can anyone at least point me to the right direction?

Ah yeah, and please CC me as I'm not subscribed to the list.

Greets,
	Hans

[1] http://www.kde-look.org/content/show.php?content=14865