I have BackUpWordPress 2.3 installed on 4 sites that are hosted on DreamHost. All 4 sites are using PHP 5.4.x FastCGI with Extra Web Security enabled, and WordPress 3.5.2. On 3 out of 4 sites, I'm seeing the warning "BackUpWordPress has detected a problem. wp-cron.php is returning a 403 Forbidden". On the 4th site, there is no warning, and a scheduled database-only backup completed successfully last night.