diff --git a/lib/OpenLayers/Ajax.js b/lib/OpenLayers/Ajax.js
index df42d33544..94d6d21538 100644
--- a/lib/OpenLayers/Ajax.js
+++ b/lib/OpenLayers/Ajax.js
@@ -248,8 +248,7 @@ OpenLayers.Ajax.Base = OpenLayers.Class({
         this.options = {
             method:       'post',
             asynchronous: true,
-            contentType:  'application/x-www-form-urlencoded',
-            encoding:     'UTF-8',
+            contentType:  'application/xml',
             parameters:   ''
         };
         OpenLayers.Util.extend(this.options, options || {});