Applet load failing with update 20

Question

Hello,
I have an applet that was working up to update 18. The applet has a web services client that now fails when being instantiated with 1.6 u20
The stack track indicates it is related to security. If anyone has any clues on what the cause is or how to troubleshoot, that would be great.
Thanks
Exception in thread "thread applet-1" java.lang.ExceptionInInitializerError
     at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
     at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
     at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
     at java.lang.reflect.Constructor.newInstance(Unknown Source)
     at java.lang.Class.newInstance0(Unknown Source)
     at java.lang.Class.newInstance(Unknown Source)
     at javax.xml.ws.spi.FactoryFinder.newInstance(Unknown Source)
     at javax.xml.ws.spi.FactoryFinder.find(Unknown Source)
     at javax.xml.ws.spi.Provider.provider(Unknown Source)
     at javax.xml.ws.Service.<init>(Unknown Source)
<snip>
Caused by: java.lang.NullPointerException
     at sun.plugin2.applet.Plugin2ClassLoader.getTrustedCodeSources(Unknown Source)
     at com.sun.deploy.security.CPCallbackHandler$ParentCallback.strategy(Unknown Source)
     at com.sun.deploy.security.CPCallbackHandler$ParentCallback.openClassPathElement(Unknown Source)
     at com.sun.deploy.security.DeployURLClassPath$JarLoader.getJarFile(Unknown Source)
     at com.sun.deploy.security.DeployURLClassPath$JarLoader.access$700(Unknown Source)
     at com.sun.deploy.security.DeployURLClassPath$JarLoader$1.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at com.sun.deploy.security.DeployURLClassPath$JarLoader.ensureOpen(Unknown Source)
     at com.sun.deploy.security.DeployURLClassPath$JarLoader.<init>(Unknown Source)
     at com.sun.deploy.security.DeployURLClassPath$3.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
     at com.sun.deploy.security.DeployURLClassPath.getLoader(Unknown Source)
     at com.sun.deploy.security.DeployURLClassPath.findResource(Unknown Source)
     at java.net.URLClassLoader$2.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at java.net.URLClassLoader.findResource(Unknown Source)
     at sun.plugin2.applet.JNLP2ClassLoader.findResource(Unknown Source)
     at java.lang.ClassLoader.getResource(Unknown Source)
     at sun.plugin2.applet.JNLP2ClassLoader.access$001(Unknown Source)
     at sun.plugin2.applet.JNLP2ClassLoader$1.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at sun.plugin2.applet.JNLP2ClassLoader.getResource(Unknown Source)
     at java.lang.ClassLoader.getResource(Unknown Source)
     at sun.plugin2.applet.JNLP2ClassLoader.access$001(Unknown Source)
     at sun.plugin2.applet.JNLP2ClassLoader$1.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at sun.plugin2.applet.JNLP2ClassLoader.getResource(Unknown Source)
     at javax.xml.bind.ContextFinder.find(Unknown Source)
     at javax.xml.bind.JAXBContext.newInstance(Unknown Source)
     at javax.xml.bind.JAXBContext.newInstance(Unknown Source)
     at com.sun.xml.internal.ws.spi.ProviderImpl$2.run(Unknown Source)
     at com.sun.xml.internal.ws.spi.ProviderImpl$2.run(Unknown Source)
     at java.security.AccessController.doPrivileged(Native Method)
     at com.sun.xml.internal.ws.spi.ProviderImpl.getEPRJaxbContext(Unknown Source)
     at com.sun.xml.internal.ws.spi.ProviderImpl.<clinit>(Unknown Source)
     ... 19 more

Answer 1

In case this helps, just before the exception is thrown the java console shows:
basic: JNLP2ClassLoader.findClass: xxx: try again ..
security: Loading certificates from Deployment session certificate store
security: Loaded certificates from Deployment session certificate store
security: Loading certificates from Internet Explorer TrustedPublisher certificate store
security: Loaded certificates from Internet Explorer TrustedPublisher certificate store
security: Validate the certificate chain using CertPath API
security: Obtain certificate collection in Root CA certificate store
security: Obtain certificate collection in Root CA certificate store
security: Start to check whether root CA is replaced
security: The root CA hasnt been replaced
security: No timestamping info available
security: Found jurisdiction list file
security: No need to checking trusted extension for this certificate
security: The CRL support is disabled
security: The OCSP support is disabled
security: This OCSP End Entity validation is disabled
security: Checking if certificate is in Deployment denied certificate store
security: Checking if certificate is in Deployment permanent certificate store
<above repeats many times>
ecurity: This OCSP End Entity validation is disabled
security: Checking if certificate is in Deployment denied certificate store
security: Checking if certificate is in Deployment permanent certificate store
basic: Removed progress listener: null
Exception in thread "thread...