When I installed Ubuntu 12.04 two days ago, I was a bit surprised to see there is no hibernate entry in Unity system menu. Hibernation is disabled by default because it is not working here and there... As most people have notebooks these days, they will prefer to hibernate their laptops over suspend. I personally prefer both and use hibernate in most cases. So, I missed Hibernate.
Here is how I get it back.
First I try the command line:
yes, yes. it is working. My notebook HP Pavilion G6-1206su hibernated and went back smoothly. So, it is working, but I have no menu entry in Unity.
Damned Unity !@!@##@@#**#&#& !
After some investigation I see there is a solution. Create new file calling gedit through gksu
gksu gedit /etc/polkit-1/localauthority/50-local.d/com.ubuntu.enable-hibernate.pkla
[Re-enable hibernate by default]
and save. After you logout and login again you will have the Hibernate entry in Unity system menu. Check yourself.