Ok here's an update. This is a real problem. It doesn't seem to be caused by any Cydia apps in particular. It happens once mobile substrate has been installed or updated and the phone has been rebooted. When I first install apps, the problem doesn't exist. However, I have to install or update Mobile Substrate with a reboot to get all apps working. And when I do that, that's when I get the error. Anyone have any solutions?