I've been trying to run some Clutter based apps, like fosfor, on Fedora 14 for awhile now. F14 uses clutter 1.2 and the upgraded ATI ddx driver does vblank signaling differently than the original ATI driver shipped with F13. Which leads to the problems I've had with getting the clutter apps to redraw properly when using a newer DDX, including the one found in updates. Fosfor would not resize windows or things would come up blank when they should be correct.
Today I came across something in a mailing list that made it work.
So I added that to my ~/.bashrc file and relogged in and since then my Clutter based apps have been working.