This is the first instance of this issue I've heard of. What browser are you using? If its internet explorer you can find out by clicking Help in the top menu and then click on About internet Explorer. I need the version number. If your on a Blackberry or personal cell phone devise, you will not be able to see the shoutbox unless the phone has java enabled. This is also the case with your computer If you do not have Java installed and running you will not be able to see any posts in the shoutbox.
Also I am going to move this topic to the Site Info/Suggestions section.