diff --git a/lib/OpenLayers/Control/Scale.js b/lib/OpenLayers/Control/Scale.js
index 6aa4d0f720..682e23d35c 100644
--- a/lib/OpenLayers/Control/Scale.js
+++ b/lib/OpenLayers/Control/Scale.js
@@ -11,11 +11,12 @@ OpenLayers.Control.Scale = Class.create();
 OpenLayers.Control.Scale.prototype = 
   Object.extend( new OpenLayers.Control(), {
     INCHES_PER_UNIT: { // borrowed from MapServer mapscale.c
-	dd: 1.0,
+	inches: 1.0,
 	ft: 12.0,
 	mi: 63360.0,
 	m: 39.3701,
-	km: 39370.1
+	km: 39370.1,
+	dd: 4374754
     },
 
     /** @type DOMElement */