My ubuntu(12.04) never shutdown. Did not help this: 1) sudo halt 2) sudo shutdown -h now 3) update grub(acpi-force)
I think it's after installaton AMD Catalyst. My friend has similar problem and he thiks it's after Gnome-shell installation.
Who have similar problem, help please!
UPDATE This is my syslog http://pastebin.com/x4VD2gH1
$ sudo /sbin/acpi_available && echo $? 0