GNOME auto-dim timeout

Since version 2.22.2 GNOME has introduced a new feature in power management - Autodimming the screen after some inactivity. Although this feature is direct copy from MacOSX, it's a really nice one. But the default timeout of 30 sec seems too short for most cases. I was wondering how to increase it and here's how:

1. Run gconf-editor. (Press Alt+F2 and enter 'gconf-editor')
2. Go to /apps/gnome-power-manager/backlight
3. Change the value of idle_dim_time. It's in seconds, 60 seems to be reasonable.

BTW, gconf-editor is like regedit in Windows. A lot of system tweakings can be done through this.