What do you mean by "*it* works"? You mean decoration in compiz? Here is the result of the command, (note my file is named a bit differently):
$ nm -D /usr/lib/libdecoration.so.0.0.0 | grep decor_property_to_quads 0000000000003340 T decor_property_to_quads I also should say I have a ATI card(ATI RV730XT [Radeon HD 4670]) and am using the driver provided by "xserver-xorg-video-radeon."
