gnome-session upower and display blanking

[John Frankish <j-frankish slb com>]

I gave gnome-3.10.x compiled from source and mostly working.

One of the things that doesn't work is display blanking, no matter what setting is used in 
gnome-control-center, the display does not blank and the screen stays burning brightly for days - on both a 
laptop and a desktop. I can blank the display using xset, but that's not the point...

The initial system uses gnome-session-3.10.1 and upower-0.9.23.

Thinking an upgrade to gnome-session-3.12.2 and upower-0.99.0 might solve the problem, I tried to recompile, 
but the configure script ignores upower >= 0.99.0

Is there a patch to fix display blanking with gnome-session-3.10.x?

How is display blanking meant to work with gnome-session-3.12.x?

Regards
John