diff --git a/root/usr/share/mozilla-mcd/thunderbird.php b/root/usr/share/mozilla-mcd/thunderbird.php
index a7c264a..e5b3308 100644
--- a/root/usr/share/mozilla-mcd/thunderbird.php
+++ b/root/usr/share/mozilla-mcd/thunderbird.php
@@ -130,6 +130,7 @@ defaultPref("mail.identity.id<?php echo $id; ?>.drafts_folder_pickup_mode", "1")
 defaultPref("mail.identity.id<?php echo $id; ?>.draft_folder", "imap://<?php echo $uid; ?>@<?php echo IMAP_SERVER; ?>/Drafts");
 defaultPref("mail.identity.id<?php echo $id; ?>.templ_folder_pickup_mode", "1");
 defaultPref("mail.identity.id<?php echo $id; ?>.stationery_folder", "imap://<?php echo $uid; ?>@<?php echo IMAP_SERVER; ?>/Templates");
+defaultPref("mail.identity.id<?php echo $id; ?>.reply_on_top", 1);
 defaultPref("mail.identity.id<?php echo $id; ?>.attach_signature", true);
 defaultPref("mail.identity.id<?php echo $id; ?>.sig_file", path_profile+path_sep+"signature"+path_sep+"email.html");
 <?php