Fixed issue related to use of magic constant only supported in PHP 5.3.

includes/classes/SWIFTMailSystem.inc

@@ -84,8 +84,8 @@ class SWIFTMailSystem implements MailSystemInterface {
   public function mail(array $message) {
 
     // Include required files.
-    require_once(dirname(__DIR__) . '/helpers/conversion.inc');
-    require_once(dirname(__DIR__) . '/helpers/utilities.inc');
+    require_once(dirname(dirname(__FILE__)) . '/helpers/conversion.inc');
+    require_once(dirname(dirname(__FILE__)) . '/helpers/utilities.inc');
 
     // Validate whether the Swift Mailer module has been configured.
     $library_path = variable_get('swiftmailer_path', SWIFTMAILER_VARIABLE_PATH_DEFAULT);
@@ -96,7 +96,7 @@ class SWIFTMailSystem implements MailSystemInterface {
     }
 
     // Include the Swift Mailer library.
-    require_once drupal_realpath($library_path . '/lib/swift_required.php');
+    require_once(drupal_realpath($library_path . '/lib/swift_required.php'));
 
     try {
 

includes/pages/swiftmailer_admin_default.inc

@@ -21,7 +21,7 @@ function swiftmailer_admin_default_page() {
 function swiftmailer_admin_default_form($form, &$form_state) {
 
   // Include helper functions.
-  require_once(dirname(__DIR__) . '/helpers/utilities.inc');
+  require_once(dirname(dirname(__FILE__)) . '/helpers/utilities.inc');
   
   $form['#tree'] = TRUE;
 
@@ -94,7 +94,7 @@ function swiftmailer_admin_default_form($form, &$form_state) {
 function swiftmailer_admin_default_form_validate($form, &$form_state) {
 
   // Include helper functions.
-  require_once(dirname(__DIR__) . '/helpers/utilities.inc');
+  require_once(dirname(dirname(__FILE__)) . '/helpers/utilities.inc');
 
   if (!swiftmailer_validate_library($form_state['values']['library']['path'])) {
     form_set_error('library][path', t('The provided path does not contain the Swift Mailer library.'));
@@ -108,7 +108,7 @@ function swiftmailer_admin_default_form_validate($form, &$form_state) {
 function swiftmailer_admin_default_form_submit($form, &$form_state) {
 
   // Include helper functions.
-  require_once(dirname(__DIR__) . '/helpers/utilities.inc');
+  require_once(dirname(dirname(__FILE__)) . '/helpers/utilities.inc');
 
   if (isset($form_state['values']['library']['path'])) {
     variable_set('swiftmailer_path', swiftmailer_validate_library($form_state['values']['library']['path']));

includes/pages/swiftmailer_admin_messages.inc

@@ -20,7 +20,7 @@ function swiftmailer_admin_messages_page() {
 function swiftmailer_admin_messages_form($form, &$form_state) {
 
   // Include helper functions.
-  require_once(dirname(__DIR__) . '/helpers/utilities.inc');
+  require_once(dirname(dirname(__FILE__)) . '/helpers/utilities.inc');
 
   $form['#tree'] = TRUE;
 

includes/pages/swiftmailer_admin_test.inc

@@ -19,7 +19,7 @@ function swiftmailer_admin_test_page() {
 function swiftmailer_admin_test_form($form, &$form_state) {
 
   // Include helper functions.
-  require_once(dirname(__DIR__) . '/helpers/utilities.inc');
+  require_once(dirname(dirname(__FILE__)) . '/helpers/utilities.inc');
 
   $form['#tree'] = TRUE;
 

includes/pages/swiftmailer_admin_transport.inc

@@ -21,7 +21,7 @@ function swiftmailer_admin_transport_page() {
 function swiftmailer_admin_transport_form($form, &$form_state) {
 
   // Include helper functions.
-  require_once(dirname(__DIR__) . '/helpers/utilities.inc');
+  require_once(dirname(dirname(__FILE__)) . '/helpers/utilities.inc');
 
   // The configuration options for the selected transport type should be
   // displayed using AJAX if JavaScript is enabled. However, we need to