Solution : Remove the "libgl1-mesa-dri" package from Beerorkid repository "deb http://www.beerorkid.com/compiz/ dapper main" which breaks the update.
gksu "upgrade-manager -c -d" should then work.
Solution : Remove the "libgl1-mesa-dri" package from Beerorkid repository "deb http:// www.beerorkid. com/compiz/ dapper main" which breaks the update.
gksu "upgrade-manager -c -d" should then work.