Comment 12 for bug 559111

Comments #10 and #11 does fix the problem, ie it reverts back to metacity. However, if I try to activate Visual effects through Appearance, it hangs on Keep settings and upon log in the problem is back. Launching gnome-appearance-properties from a terminal gives the following output when changing from None to Normal under Visual effects:

martin@martin-desktop:~$ gnome-appearance-properties
There is not a graphics driver available for your system which supports the composite extension, or the current driver already supports it.

Couldn't find a perfect decorator match; trying all decorators
Found no decorator to start
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I then launched Synaptics and discovered that the package compiz and compiz-gnome wasn't installed. I installed them and tried the above again, and the last two messages isn't displayed anymore. It still hangs on Keep settings dialog, but upon logging out and logging in Compiz seems to be working. The Visual effects are left in Normal and not changed back to None as was the case before.