diff --git a/program/include/iniset.php b/program/include/iniset.php
index 2be15b1a5..fda13e9cf 100755
--- a/program/include/iniset.php
+++ b/program/include/iniset.php
@@ -53,6 +53,7 @@ if (set_include_path($include_path) === false) {
 ini_set('session.name', 'roundcube_sessid');
 ini_set('session.use_cookies', 1);
 ini_set('session.only_use_cookies', 1);
+ini_set('session.cookie_secure', ($_SERVER['HTTPS'] && ($_SERVER['HTTPS'] != 'off')));
 ini_set('error_reporting', E_ALL&~E_NOTICE);
 set_magic_quotes_runtime(0);