I will add a feature request for this.
in the man time, yiou would need to modify the code provided earlier to store the sessions you wish to retain in application variables, then reset them once the session restarts. For example, if the user session variable is named userID:
<?php
// Initialize the session.
// If you are using session_name("something"), don't forget it now!
session_start();
$userID = $_SESSION['userID'];
// Unset all of the session variables.
$_SESSION = array();
// If it's desired to kill the session, also delete the session cookie.
// Note: This will destroy the session, and not just the session data!
if (ini_get("session.use_cookies")) {
$params = session_get_cookie_params();
setcookie(session_name(), '', time() - 42000,
$params["path"], $params["domain"],
$params["secure"], $params["httponly"]
);
}
// Finally, destroy the session.
session_destroy();
session_regenerate_id();
$_SESSION['userID'] = $userID;
?>