The following error is thrown during cron runs:
Warning: Missing argument 2 for wpdb::prepare(), called in /site/wp-content/plugins/user-messages/model/MailDAO.php on line 38 and defined in /site/wp-includes/wp-db.php on line 990.
It occurs when someone sends a private message to another user on the site.
Starting from WordPress 3.5.x the
prepare() method requires second argument, even as an empty array.
Please release an update to the plugin to make it fully compatible with WP 3.5.x.