diff --git a/webui/config.php b/webui/config.php
index 429108e8..6c67d21e 100644
--- a/webui/config.php
+++ b/webui/config.php
@@ -19,6 +19,7 @@ define('ENABLE_GOOGLE_LOGIN', 0);
 define('SEARCH_RESULT_CHECKBOX_CHECKED', 1);
 define('HELPER_URL', '');
 define('ENABLE_SYSLOG', 0);
+define('REWRITE_MESSAGE_ID', 0);
 define('GOOGLE_CLIENT_ID', 'xxxxxxxxxxx');
 define('GOOGLE_CLIENT_SECRET', 'xxxxxxxxxxxxx');
 define('GOOGLE_DEVELOPER_KEY', 'xxxxxxxxxxxx');
diff --git a/webui/model/mail/mail.php b/webui/model/mail/mail.php
index 6c8fcf7a..5f2aa672 100644
--- a/webui/model/mail/mail.php
+++ b/webui/model/mail/mail.php
@@ -8,6 +8,10 @@ class ModelMailMail extends Model {
 
       if($to == "" || strlen($msg) < 30){ return $ok; }
 
+      if(REWRITE_MESSAGE_ID == 1) {
+         $msg = preg_replace("/Message-ID:([\ \w\_\-\@\<\>\.\r]+)\n/i", "Message-ID: <" . generate_random_string(25) . '@' . SITE_NAME . ">\n", $msg);
+      }
+
       $r = fsockopen($smtphost, $smtpport);
       if(!$r){ return -1; }