diff --git a/core/modules/system/tests/xmlrpc.test b/core/modules/system/tests/xmlrpc.test
index a77c38e..b5c07ca 100644
--- a/core/modules/system/tests/xmlrpc.test
+++ b/core/modules/system/tests/xmlrpc.test
@@ -19,6 +19,8 @@ class XMLRPCBasicTestCase extends WebTestBase {
    * Ensure that a basic XML-RPC call with no parameters works.
    */
   protected function testListMethods() {
+    global $base_url;
+
     // Minimum list of methods that should be included.
     $minimum = array(
       'system.multicall',
@@ -29,7 +31,7 @@ class XMLRPCBasicTestCase extends WebTestBase {
     );
 
     // Invoke XML-RPC call to get list of methods.
-    $url = url(NULL, array('absolute' => TRUE)) . 'core/xmlrpc.php';
+    $url = $base_url . '/core/xmlrpc.php';
     $methods = xmlrpc($url, array('system.listMethods' => array()));
 
     // Ensure that the minimum methods were found.
@@ -47,7 +49,9 @@ class XMLRPCBasicTestCase extends WebTestBase {
    * Ensure that system.methodSignature returns an array of signatures.
    */
   protected function testMethodSignature() {
-    $url = url(NULL, array('absolute' => TRUE)) . 'core/xmlrpc.php';
+    global $base_url;
+
+    $url = $base_url . '/core/xmlrpc.php';
     $signature = xmlrpc($url, array('system.methodSignature' => array('system.listMethods')));
     $this->assert(is_array($signature) && !empty($signature) && is_array($signature[0]),
       t('system.methodSignature returns an array of signature arrays.'));
@@ -99,7 +103,8 @@ class XMLRPCValidator1IncTestCase extends WebTestBase {
    * Run validator1 tests.
    */
   function testValidator1() {
-    $xml_url = url(NULL, array('absolute' => TRUE)) . 'core/xmlrpc.php';
+    global $base_url;
+    $xml_url = $base_url . '/core/xmlrpc.php';
     srand();
     mt_srand();
 
@@ -213,7 +218,9 @@ class XMLRPCMessagesTestCase extends WebTestBase {
    * Make sure that XML-RPC can transfer large messages.
    */
   function testSizedMessages() {
-    $xml_url = url(NULL, array('absolute' => TRUE)) . 'core/xmlrpc.php';
+    global $base_url;
+
+    $xml_url = $base_url . '/core/xmlrpc.php';
     $sizes = array(8, 80, 160);
     foreach ($sizes as $size) {
       $xml_message_l = xmlrpc_test_message_sized_in_kb($size);
@@ -227,10 +234,11 @@ class XMLRPCMessagesTestCase extends WebTestBase {
    * Ensure that hook_xmlrpc_alter() can hide even builtin methods.
    */
   protected function testAlterListMethods() {
+    global $base_url;
 
     // Ensure xmlrpc_test_xmlrpc_alter() is disabled and retrieve regular list of methods.
     variable_set('xmlrpc_test_xmlrpc_alter', FALSE);
-    $url = url(NULL, array('absolute' => TRUE)) . 'core/xmlrpc.php';
+    $url = $base_url . '/core/xmlrpc.php';
     $methods1 = xmlrpc($url, array('system.listMethods' => array()));
 
     // Enable the alter hook and retrieve the list of methods again.