--- messaging_phpmailer.module.orig	2009-01-22 23:46:05.000000000 -0500
+++ messaging_phpmailer.module	2009-01-22 23:55:43.000000000 -0500
@@ -82,6 +82,15 @@
     $function($mailkey, $to, $subject, $body, $from, $headers);
   }
 
+	drupal_set_message(print_r($headers,true));
+	if(array_key_exists('Message-ID',$headers) && !empty($headers['Message-ID'])) {
+		$mail->AddCustomHeader('Message-ID: ' . $headers['Message-ID']);
+	}
+
+	if(array_key_exists('Reply-To',$headers) && !empty($headers['Reply-To'])) {
+		$mail->AddReplyTo($headers['Reply-To']);
+	}
+
   $mail->From = $defaults['From'];
   $mail->FromName = $defaults['From'];
   $mail->AddAddress($to);
@@ -100,4 +109,4 @@
  */
 function theme_messaging_phpmailer($subject, $body, $from, $mailkey) {
   return array($subject, $body);
-}
\ No newline at end of file
+}