I switched from Ubuntu 10.04 to Kubuntu 10.04 about 5 days ago and while I've pretty much found my way around KDE 4, there is one thing I can't same to figure out how to do. After I've added a wallpaper from my Pictures folder in Desktop Activity Settings, I can't seem to be able to remove it. In GNOME there was a button that removed the selected wallpaper from the appearance settings, but KDE doesn't seem to have something like that. I like to remove the wallpapers that I'm not using to keep it nice and tidy. Is there any way to do this that I may have overlooked?

This is available in KDE 4.5, I am not sure about earlier versions.