diff --git a/lib/OpenLayers/Ajax.js b/lib/OpenLayers/Ajax.js
index 4f2e7b9aae..8eee0b9742 100644
--- a/lib/OpenLayers/Ajax.js
+++ b/lib/OpenLayers/Ajax.js
@@ -283,7 +283,7 @@ OpenLayers.Ajax.Request = OpenLayers.Class(OpenLayers.Ajax.Base, {
     initialize: function(url, options) {
         OpenLayers.Ajax.Base.prototype.initialize.apply(this, [options]);
         
-        if (OpenLayers.ProxyHost && OpenLayers.String.startsWith(uri, "http")) {
+        if (OpenLayers.ProxyHost && OpenLayers.String.startsWith(url, "http")) {
             url = OpenLayers.ProxyHost + encodeURIComponent(url);
         }