diff --git a/library/Zend/XmlRpc/Server.php b/library/Zend/XmlRpc/Server.php
index b25e25174c..505e54533a 100644
--- a/library/Zend/XmlRpc/Server.php
+++ b/library/Zend/XmlRpc/Server.php
@@ -465,7 +465,7 @@ public function getRequest()
     public function setResponseClass($class)
     {
         if (!class_exists($class) ||
-            ($c = new ReflectionClass($class) && !$c->isSubclassOf('Zend_XmlRpc_Response'))) {
+            (($c = new ReflectionClass($class)) && !$c->isSubclassOf('Zend_XmlRpc_Response'))) {
 
             require_once 'Zend/XmlRpc/Server/Exception.php';
             throw new Zend_XmlRpc_Server_Exception('Invalid response class');