IES-like lights in Cycles I have been consistently trying and failing to recreate the techniques described in the links to create an IES like textured light effect with Cycles Spotlight lamps using a Color Ramp node.

http://blenderartists.org/forum/showthread.php?264052-IES-Like-Lights-in-Cycles-Architectural-Lighting or 

http://www.elysiun.com/forum/showthread.php?264052-IES-Like-Lights-in-Cycles-Architectural-Lighting/page2

According to the images you need the Dot Product between the Normal with Incoming connected to a Color Ramp node; however recreating the described node setup does not yield the same desired effect as shown bellow.



Using Add instead of Dot Product seems to show some effect, but it's not the expected result.



Those images seem to be from older versions of Blender, using 2.65 and above I have never been able to achieve that effect.
Did something change internally that broke these techniques, or is there a new workflow to achieve the effect currently? 

Did I miss something obvious? Hopefully someone with better math knowledge can solve this.
I did miss something obvious, thanks to Carlos comment I solved what was wrong with my scene.

The problem was not with the node setup itself, but with the object data. Light type must be an Area Light, not a Spot Lamp.

Using the correct area light type now yields expected results.