diff --git a/htmlmail.admin.inc b/htmlmail.admin.inc
index fcfea09..0d1ba07 100644
--- a/htmlmail.admin.inc
+++ b/htmlmail.admin.inc
@@ -184,6 +184,16 @@ function htmlmail_admin_settings() {
     '#title' => t('Step 3'),
     '#collapsible' => FALSE,
   );
+  if (!module_exists('mailmime')) {
+    $form['filter']['htmlmail_html_with_plain'] = array(
+      '#type' => 'checkbox',
+      '#title' => t('Provide simple plain/text alternative of the HTML mail.'),
+      '#default_value' => variable_get('htmlmail_html_with_plain', FALSE),
+      '#description' => t('This may increase the quality of your outgoing emails for the spam filters. If you need image handling and more sophisticated plain text version, check !mailmime.', array(
+        '!mailmime' => l(t('Mailmime'), 'https://www.drupal.org/project/mailmime', array('attributes' => array('target' => '_blank'))),
+      ))
+    );
+  }
   $form['filter']['htmlmail_postfilter'] = array(
     '#type' => 'select',
     '#title' => t('Post-filtering'),
diff --git a/htmlmail.mail.inc b/htmlmail.mail.inc
index 16fe7cd..b424cf1 100644
--- a/htmlmail.mail.inc
+++ b/htmlmail.mail.inc
@@ -120,6 +120,21 @@ class HTMLMailSystem implements MailSystemInterface {
       else {
         $message['headers']['Content-Type'] = 'text/html; charset=utf-8';
         $message['body'] = $body;
+        if (variable_get('htmlmail_html_with_plain', FALSE)) {
+          $boundary = uniqid('np');
+          $message['headers']['Content-Type'] = "multipart/alternative;boundary=" . $boundary . "\r\n";
+          $html = $message['body'];
+          $raw_message = 'This is a MIME encoded message.';
+          $raw_message .= "\r\n\r\n--" . $boundary . "\r\n";
+          $raw_message .= "Content-type: text/plain;charset=utf-8\r\n\r\n";
+          $raw_message .= mailsystem_html_to_text($html);
+          $raw_message .= "\r\n\r\n--" . $boundary . "\r\n";
+          $raw_message .= "Content-type: text/html;charset=utf-8\r\n\r\n";
+          $raw_message .= $html;
+          $raw_message .= "\r\n\r\n--" . $boundary . "--";
+          $message['body'] = $raw_message;
+
+        }
       }
     }
     else {