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Is there any better way to refresh gnome-panel?

killall gnome-panel works but, not only does everything flash in and out of existence but my gaim window pops up out of the panel and doesn't hide itself again.

I've written a Perl wallpaper changer which updates its launcher to show the current image name as a tooltip but the only way I've found to update the tooltip is to kill gnome-panel. --denishowe