diff --git a/lib/Doctrine/Resource.php b/lib/Doctrine/Resource.php
index f433dfd38..486296586 100644
--- a/lib/Doctrine/Resource.php
+++ b/lib/Doctrine/Resource.php
@@ -34,7 +34,7 @@
 class Doctrine_Resource
 {
     protected $_config = null;
-    protected $_defaultFormat = 'xml';
+    const FORMAT = 'json';
     
     public function __construct($config)
     {
@@ -48,10 +48,6 @@ class Doctrine_Resource
                 $this->loadDoctrine = true;
             }
         }
-        
-        if (!$this->getConfig()->has('format') OR !$this->getConfig()->get('format')) {
-            $this->getConfig()->set('format', $this->_defaultFormat);
-        }
     }
     
     public function getConfig($key = null)
diff --git a/lib/Doctrine/Resource/Client.php b/lib/Doctrine/Resource/Client.php
index c2bd95a55..a7a0d643a 100644
--- a/lib/Doctrine/Resource/Client.php
+++ b/lib/Doctrine/Resource/Client.php
@@ -61,7 +61,7 @@ class Doctrine_Resource_Client extends Doctrine_Resource
     
     public function loadDoctrine()
     {
-        $path = '/tmp/' . md5(serialize($this->getConfig()));
+        $path = '/tmp/' . $this->getClientKey();
         $classesPath = $path.'.classes.php';
         
         if (file_exists($path)) {
@@ -73,13 +73,13 @@ class Doctrine_Resource_Client extends Doctrine_Resource
             $schema = $request->execute();
             
             if ($schema) {
-                file_put_contents($path, Doctrine_Parser::dump($schema, 'xml'));
+                file_put_contents($path, Doctrine_Parser::dump($schema, Doctrine_Resource::FORMAT));
             }
         }
         
         if (file_exists($path) && $schema) {
             $import = new Doctrine_Import_Schema();
-            $schema = $import->buildSchema($path, 'xml');
+            $schema = $import->buildSchema($path, Doctrine_Resource::FORMAT);
             
             if (!file_exists($classesPath)) {
                 $build = "<?php\n";
@@ -98,6 +98,11 @@ class Doctrine_Resource_Client extends Doctrine_Resource
         }
     }
     
+    public function getClientKey()
+    {
+        return md5(Doctrine_Resource::FORMAT.serialize($this->getConfig()));
+    }
+    
     public function getTable($table)
     {
         static $instance;
diff --git a/lib/Doctrine/Resource/Request.php b/lib/Doctrine/Resource/Request.php
index 0f2148a14..f0f4ed826 100644
--- a/lib/Doctrine/Resource/Request.php
+++ b/lib/Doctrine/Resource/Request.php
@@ -44,13 +44,15 @@ class Doctrine_Resource_Request extends Doctrine_Resource_Params
     {
         $url  = $this->getConfig()->get('url');
         
-        $request = array('xml' => Doctrine_Parser::dump($this->getAll(), 'xml'));
+        $request = array('request' => Doctrine_Parser::dump($this->getAll(), $this->getFormat()));
+        
+        $header[0] = 'Accept: ' . $this->getFormat();
         
         $ch = curl_init(); 
         curl_setopt($ch, CURLOPT_URL, $url);
         curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
         curl_setopt($ch, CURLOPT_POST, 1);
-        
+        curl_setopt($ch, CURLOPT_HTTPHEADER, $header);
         curl_setopt($ch, CURLOPT_POSTFIELDS, $request);
         $response = curl_exec($ch);
         
@@ -63,7 +65,7 @@ class Doctrine_Resource_Request extends Doctrine_Resource_Params
         $array = array();
         
         if ($response) {
-            $array = Doctrine_Parser::load($response, $this->getConfig()->get('format'));
+            $array = Doctrine_Parser::load($response, $this->getFormat());
         }
         
         if (isset($array['error'])) {
@@ -72,4 +74,9 @@ class Doctrine_Resource_Request extends Doctrine_Resource_Params
         
         return $array;
     }
+    
+    public function getFormat()
+    {
+        return ($this->getConfig()->has('format') && $this->getConfig()->get('format')) ? $this->getConfig()->get('format'):Doctrine_Resource::FORMAT;
+    }
 }
\ No newline at end of file
diff --git a/lib/Doctrine/Resource/Server.php b/lib/Doctrine/Resource/Server.php
index 1b3e9ad4c..17d1c36a0 100644
--- a/lib/Doctrine/Resource/Server.php
+++ b/lib/Doctrine/Resource/Server.php
@@ -171,9 +171,9 @@ class Doctrine_Resource_Server extends Doctrine_Resource
         $models = $this->getConfig('models') ? $this->getConfig('models'):array();
         
         $export = new Doctrine_Export_Schema();
-        $export->exportSchema($path, 'xml', null, $models);
+        $export->exportSchema($path, $this->getFormat(), null, $models);
         
-        $schema = Doctrine_Parser::load($path, 'xml');
+        $schema = Doctrine_Parser::load($path, $this->getFormat());
         
         unlink($path);
         
@@ -182,11 +182,11 @@ class Doctrine_Resource_Server extends Doctrine_Resource
     
     public function execute(array $r)
     {
-        if (!isset($r['xml'])) {
-            throw new Doctrine_Resource_Exception('You must specify an xml string in your request');
+        if (!isset($r['request'])) {
+            throw new Doctrine_Resource_Exception('You must specify a request '.$this->getFormat().' string in your request');
         }
         
-        $requestArray = Doctrine_Parser::load($r['xml']);
+        $requestArray = Doctrine_Parser::load($r['request'], $this->getFormat());
         
         $request = new Doctrine_Resource_Request($requestArray);
         
@@ -200,7 +200,7 @@ class Doctrine_Resource_Server extends Doctrine_Resource
             if ($this->validate($errors)) {
                 $result = $this->$funcName($request);
                 
-                return Doctrine_Parser::dump($result, 'xml');
+                return Doctrine_Parser::dump($result, $this->getFormat());
             }
         } else {
             throw new Doctrine_Resource_Exception('Unknown Doctrine Resource Server function');
@@ -222,6 +222,13 @@ class Doctrine_Resource_Server extends Doctrine_Resource
     {
         $error = array('error' => $e->getMessage());
         
-        return Doctrine_Parser::dump($error);
+        return Doctrine_Parser::dump($error, $this->getFormat());
+    }
+    
+    public function getFormat()
+    {
+        $headers = getallheaders();
+        
+        return isset($headers['Accept']) ? $headers['Accept']:Doctrine_Resource::FORMAT;
     }
 }
\ No newline at end of file
diff --git a/playground/index.php b/playground/index.php
index 764990286..84188199f 100644
--- a/playground/index.php
+++ b/playground/index.php
@@ -1,5 +1,27 @@
 <?php
 require_once('playground.php');
-require_once('connection.php');
-require_once('models.php');
-require_once('data.php');
\ No newline at end of file
+
+if (isset($_REQUEST['server'])) {
+    require_once('connection.php');
+    require_once('models.php');
+    require_once('data.php');
+    
+    $name = 'Doctrine_Resource_Playground';
+    $config = array('models'    =>  $tables);
+                    
+    $server = Doctrine_Resource_Server::getInstance($name, $config);
+    $server->run($_REQUEST);
+    
+} else {
+    $url = 'http://localhost/~jwage/doctrine_trunk/playground/index.php?server';
+    $config = array('format' => 'json');
+    
+    // Instantiate a new client
+    $client = Doctrine_Resource_Client::getInstance($url, $config);
+    
+    $query = new Doctrine_Resource_Query();
+    
+    $users = $query->from('User u, u.Phonenumber p, u.Email e, u.Address a')->execute();
+    
+    print_r($users->toArray(true));
+}
\ No newline at end of file