diff --git a/includes/mimemail.mail.inc b/includes/mimemail.mail.inc
index f71ffcf..19e547c 100644
--- a/includes/mimemail.mail.inc
+++ b/includes/mimemail.mail.inc
@@ -25,7 +25,7 @@ class MimeMailSystem implements MailSystemInterface {
     }
 
     if (preg_match('/plain/', $message['headers']['Content-Type'])) {
-      $message['body'] = check_markup($message['body'], variable_get('mimemail_format', variable_get('filter_default_format', FILTER_DEFAULT_FORMAT)));
+      $message['body'] = check_markup($message['body'], variable_get('mimemail_format', variable_get('filter_default_format', 1)));
     }
 
     $engine = variable_get('mimemail_engine', 'mimemail');