diff --git a/src/tilesource.js b/src/tilesource.js
index 0120e515..7448ba42 100644
--- a/src/tilesource.js
+++ b/src/tilesource.js
@@ -292,6 +292,9 @@ $.TileSource.prototype = {
         }
 
         callback = function( data ){
+            if( typeof(data) === "string" ) {
+                data = $.parseXml( data );
+            }
             var $TileSource = $.TileSource.determineType( _this, data, url );
             if ( !$TileSource ) {
                 _this.raiseEvent( 'open-failed', { message: "Unable to load TileSource", source: url } );