Security problems running Java apps? In its Update 51 Java 7 raised the security restrictions and does not accept university "self-issued" security certificates. We are working at resolving this problem, but a temporary fix is to add the http://carma.astro.umd.edu site to the Java Exception site list in your Java.
To do so bring up the Java Control Panel (found under System Preferences in a Mac, or here in Windows, or by typing 'java -viewer' in Linux and closing the 'Java Cache Viewer' window). Click on the 'Security' tab. Using the 'Edit Site List...' button add 'http://carma.astro.umd.edu' to the list of sites. The system will complain that it is not a 'secure' https connection, but confirm it anyway. That should fix any problems with security exceptions.