diff --git a/program/steps/mail/show.inc b/program/steps/mail/show.inc
index 8b6ce5809..3cdf2c9a5 100644
--- a/program/steps/mail/show.inc
+++ b/program/steps/mail/show.inc
@@ -42,9 +42,6 @@ if ($_GET['_uid']) {
     
   $mbox_name = $IMAP->get_mailbox_name();
   
-  // calculate Etag for this request
-  $etag = md5($MESSAGE->uid.$mbox_name.session_id().intval($MESSAGE->headers->mdn_sent).intval($MESSAGE->is_safe).intval($PRINT_MODE));
-
   // check known senders to display images
   if (!$MESSAGE->is_safe 
       && !empty($MESSAGE->sender['mailto'])
@@ -57,6 +54,9 @@ if ($_GET['_uid']) {
     }
   }
 
+  // calculate Etag for this request
+  $etag = md5($MESSAGE->uid.$mbox_name.session_id().intval($MESSAGE->headers->mdn_sent).intval($MESSAGE->is_safe).intval($PRINT_MODE));
+
   // allow caching, unless remote images are present
   if ((bool)$MESSAGE->is_safe)
     send_nocacheing_headers();