diff --git a/includes/phpmailer.mimemail.inc b/includes/phpmailer.mimemail.inc
index ccac3bf..ba02f5a 100644
--- a/includes/phpmailer.mimemail.inc
+++ b/includes/phpmailer.mimemail.inc
@@ -68,7 +68,7 @@ function mimemail_phpmailer_send($message) {
       $message['headers']['Reply-To'] = $from['mail'];
     }
 
-    $message['headers']['Subject'] = $message['subject'];
+    $message['headers']['Subject'] = mime_header_encode($message['subject']);
 
     // FIXME SpamAssassin says INVALID_MSGID to PHPMailer's generated Message-ID. 06/04/2009 smk
 //    if (!isset($message['headers']['Message-ID'])) {