Comment 2 for bug 467631

Found a workaround here: http://forum.compiz.org/showthread.php?t=5668

"The GNOME workspace switcher and window list will probably have to be patched to integrate well with viewports. That's what I hear Ubuntu 7.10 did, anyway. But you can at least eliminate the multiple cubes thing by setting ccsm->General Options->Desktop Size->Number of Desktops to 1."

It appears this is a regression from a while back. Not sure why it arose when upgrading from Ibex to Jaunty - possibly this counts as a problem with the upgrade tool?