compizconfig-backend-gconf (compiz gconf backend)
 
This is the GConf backend for CompizConfig.  It uses the GConf 
configuration system to store the compiz configuration and provides 
integration into the desktop environment.
If you compiled compiz against metacity, specified 'gtk-window-decorator'
as the window decoration plugin in ccsm, use metacity, and want to put 
shadows around windows borders, compizconfig-backend-gconf is needed.

If you want shadows around windows borders of metacity, then rebuild 
compiz against metacity, install this, and choose the GConf Configuration
Backend in the ccsm preferences.
 
This requires GConf and libcompizconfig.