Email does not update when changed from edit button on checkout page

This is a fix I am using. You can add it to any module since it only uses hook_user_update. I haven't done much testing with it so use as a starting point.

/**
 * Implements hook_user_update().
 */
function uc_cart_user_update(&$edit, $account, $category) {
  // Load an order from the session, if available.
  if (isset($_SESSION['cart_order'])) {
    $order = uc_order_load($_SESSION['cart_order']);
    if ($order && (uc_order_status_data($order->order_status, 'state') == 'in_checkout') &&
          ($account->uid == $order->uid)) {
      //update the users primary order email if it has changed
      if ($order->primary_email != $account->mail) {
        $order->primary_email = $account->mail;
        uc_order_save($order);        
      }
    }
  }
}