I run Ubuntu 10.10 (Maverick). I had removed Compiz 0.8.x from my system so I could try out Compiz 0.9.x. I then decided that I wanted Compiz 0.8.x back, so I installed the packages from aptitude. Now, when I try to start Compiz, I get this error:

compiz: symbol lookup error: /usr/lib/compiz/libdecoration.so: undefined symbol: decor_property_to_quads

Using the command "readelf /usr/lib/compiz/libdecoration.so -s", I see that that symbol is present:

24: 00000000     0 FUNC    GLOBAL DEFAULT  UND decor_property_to_quads

Aptitude reports that my Compiz core packages (like compiz, compiz-core, compiz-plugins, etc.) are at version 1:0.8.6-0ubuntu9.1.

Does anyone have any ideas why Compiz is reporting this error, and/or what I can do to fix it? I cannot run Compiz, because this error causes Compiz to abort, even if the "Window Decoration" plugin is not enabled.