Hi,
We recently got a few servers blacklisted due to spam coming from our RVSiteBuilder tryout websites ( we have them on different servers for different client groups), and I can confirm that anyone who signs up for a tryout account can setup a PHP script to send email using the mail(), or sendmail options. The only restriction is that the servers have sending limits, but spammer still have a full 30 days (or however long the tryout accounts are active) to send spam, without any regulation from anyone.
Please disable PHP and JS scripts, as well as mail functionality for tryout demo users.