--- /dev/null
+--- dokuwiki-2008-05-05/inc/common.php~ 2008-11-20 16:13:06.616720562 +0200
++++ dokuwiki-2008-05-05/inc/common.php 2008-11-20 16:12:51.042753759 +0200
+@@ -1009,7 +1009,20 @@
+ $from = str_replace('@NAME@',$INFO['userinfo']['name'],$from);
+ $from = str_replace('@MAIL@',$INFO['userinfo']['mail'],$from);
+
+- mail_send($to,$subject,$text,$from,'',$bcc);
++ $headers = array();
++ // add mail headers to identify page changes in same mail thread
++ $file = wikiFN($id);
++ $cur = @filemtime($file);
++ $headers['Message-Id'] = "$id?rev=$cur";
++ if ($rev) {
++ $headers['In-Reply-To'] = "$id?rev=$rev";
++ }
++ $h = '';
++ foreach ($headers as $k => $v) {
++ $h .= sprintf("%s: %s%s", $k, $v, MAILHEADER_EOL);
++ }
++
++ mail_send($to,$subject,$text,$from,'' ,$bcc, $h);
+ }
+
+ /**