I upgraded my Lenovo 3000 V200 Ubuntu 11.10 to 12.04 just recently. And I noticed that my favorite “hibernate” is missing. So… I read and modified the kernel sources.. recompiled…… JUST KIDDING!!! I actually googled and found this thread (http://askubuntu.com/questions/94754/how-to-modify-policykit-to-allow-hibernation-in-upower) and it works!!
Just create or modify this file using your favorite file editor (vim works for me!)
[Re-enable hibernate by default] Identity=unix-user:* Action=org.freedesktop.upower.hibernate ResultActive=yes
A restart (power cycle) to apply the changes and then wooolaaa!!! “hibernate” is back!!