diff --git includes/mail.inc includes/mail.inc
index 58a7b58..fd4981a 100644
--- includes/mail.inc
+++ includes/mail.inc
@@ -165,7 +165,7 @@ function drupal_mail($module, $key, $to, $language, $params = array(), $from = N
  *
  * @code
  * array(
- *   'default-system' => 'DrupalMailSend',
+ *   'default-system' => 'DefaultMailSystem',
  *   'user' => 'DevelMailLog',
  * );
  * @endcode
@@ -175,7 +175,7 @@ function drupal_mail($module, $key, $to, $language, $params = array(), $from = N
  *
  * @code
  * array(
- *   'default-system' => 'DrupalMailSend',
+ *   'default-system' => 'DefaultMailSystem',
  *   'user' => 'DevelMailLog',
  *   'contact_page_autoreply' => 'DrupalDevNullMailSend',
  * );
@@ -197,7 +197,7 @@ function drupal_mail_sending_system($module, $key) {
   $instances = &drupal_static(__FUNCTION__, array());
 
   $id = $module . '_' . $key;
-  $configuration = variable_get('mail_sending_system', array('default-system' => 'DrupalMailSend'));
+  $configuration = variable_get('mail_sending_system', array('default-system' => 'DefaultMailSystem'));
 
   // Look for overrides for the default class, starting from the most specific
   // id, and falling back to the module name.
diff --git modules/simpletest/simpletest.test modules/simpletest/simpletest.test
index 02b868a..c363783 100644
--- modules/simpletest/simpletest.test
+++ modules/simpletest/simpletest.test
@@ -302,7 +302,7 @@ class SimpleTestMailCaptureTestCase extends DrupalWebTestCase {
     $this->assertEqual(count($captured_emails), 0, t('The captured e-mails queue is empty.'), t('E-mail'));
 
     // Send the e-mail.
-    $response = drupal_mail_send($message);
+    $response = drupal_mail_sending_system('simpletest', 'drupal_mail_test')->mail($message);
 
     // Ensure that there is one e-mail in the captured e-mails array.
     $captured_emails = $this->drupalGetMails();
@@ -323,7 +323,7 @@ class SimpleTestMailCaptureTestCase extends DrupalWebTestCase {
         'to' => $this->randomName(32) . '@example.com',
         'body' => $this->randomString(512),
       );
-      drupal_mail_send($message);
+      drupal_mail_sending_system('drupal_mail_test', $index)->mail($message);
     }
 
     // There should now be 6 e-mails captured.
@@ -340,7 +340,7 @@ class SimpleTestMailCaptureTestCase extends DrupalWebTestCase {
 
     // Send the last e-mail again, so we can confirm that the drupalGetMails-filter
     // correctly returns all e-mails with a given property/value.
-    drupal_mail_send($message);
+    drupal_mail_sending_system('drupal_mail_test', $index)->mail($message);
     $captured_emails = $this->drupalGetMails(array('id' => 'drupal_mail_test_4'));
     $this->assertEqual(count($captured_emails), 2, t('All e-mails with the same id are returned when filtering by id.'), t('E-mail'));
   }