We need to improve on error message when JNLP file missing security tag and containing resource tag pointing to signed jars. The current error message does not help user correct their JNLP file.

java.lang.SecurityException: attempted to open sandboxed jar http://javaweb.sfbay.sun.com/~nn136682/lib/SignedArcTest.jar as a Trusted-Library
   at com.sun.deploy.security.CPCallbackHandler$ParentElement.checkResource(CPCallbackHandler.java:356)
   at com.sun.deploy.security.DeployURLClassPath$JarLoader.checkResource(DeployURLClassPath.java:802)
   at com.sun.deploy.security.DeployURLClassPath$JarLoader.getResource(DeployURLClassPath.java:902)
   at com.sun.deploy.security.DeployURLClassPath.getResource(DeployURLClassPath.java:229)
   at java.net.URLClassLoader$1.run(URLClassLoader.java:358)
   at java.net.URLClassLoader$1.run(URLClassLoader.java:355)
   at java.security.AccessController.doPrivileged(Native Method)
   at java.net.URLClassLoader.findClass(URLClassLoader.java:354)
   at com.sun.jnlp.JNLPClassLoader.findClass(JNLPClassLoader.java:302)
   at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
   at java.lang.ClassLoader.loadClass(ClassLoader.java:410)
   at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
   at com.sun.javaws.Launcher.doLaunchApp(Launcher.java:1527)