I have decided to replace Xfce4-power-manager with gnome-power-manager in Lubuntu 12.04 (didn't knew how to disable the tray icon in fact), which I did using synaptic, and now it shows:
gnome-power-manager is nowhere to be found.
Searching for the file, I only see this:
There is only
Shouldn't be a
gnome-power-manager executable and with options that should look like in this question?