The web version of sobees (which is built on Silverlight) does unfortunately not work properly with the latest version of Firefox (3.6). Since the previous versions of Firefox were, in certain cases, sending wrong mouse coordinates to plugins like Silverlight (the iframe apparently being one of them), Microsoft had implemented a workaround in their code in order to solve the problem. However, Firefox fixed the bug in their latest version (3.6), breaking Microsoft's workaround and creating the issue some of you encountered.
Microsoft is aware of this issue and is working on a solution. We will inform you as soon as we get new information. Sorry for this inconvenience!