JNLP Already initialized, NullPointerException with icedtea6-plugin?

I have a trusted applet, and I'm getting the following behavior with开发者_运维百科 OpenJDK and icedtea6-plugin:

Initializing JVM...
NOT IMPLEMENTED: virtual nsresult IcedTeaPluginInstance::Start()
Jar string: applets/MyApplet.jar
jars length: 1
JNLPRuntime already initialized
java.lang.NullPointerException
    at net.sourceforge.jnlp.tools.JarSigner.verifyJars(JarSigner.java:192)
    at net.sourceforge.jnlp.runtime.JNLPClassLoader.verifyJars(JNLPClassLoader.java:626)
    at net.sourceforge.jnlp.runtime.JNLPClassLoader.initializeResources(JNLPClassLoader.java:302)
    at net.sourceforge.jnlp.runtime.JNLPClassLoader.<init>(JNLPClassLoader.java:134)
    at net.sourceforge.jnlp.runtime.JNLPClassLoader.getInstance(JNLPClassLoader.java:191)
    at net.sourceforge.jnlp.Launcher.createApplet(Launcher.java:445)
    at net.sourceforge.jnlp.Launcher.getApplet(Launcher.java:418)
    at net.sourceforge.jnlp.Launcher$TgThread.run(Launcher.java:597)
netx: Initialization Error: Could not initialize applet. (net.sourceforge.jnlp.LaunchException Fatal: Initialization Error: A fatal error occurred while trying to verify jars.)
netx: Initialization Error: Could not initialize applet. (net.sourceforge.jnlp.LaunchException Fatal: Initialization Error: A fatal error occurred while trying to verify jars.)

The Sun JVM and plugin work fine. What could be going wrong?

It's just an OpenJDK issue. It's supposed to be fixed in the latest version (not in repos).