From the applet compatibility test suite runs, the Java charting applet at http://www.prophet.net/analyze/javacharts.jsp fails to run with the new Java Plug-In. The reason appears to be a NullPointerException thrown from deep within the applet's (obfuscated) code during startup:

java.lang.reflect.InvocationTargetException
at com.sun.deploy.util.DeployAWTUtil.invokeAndWait(DeployAWTUtil.java:116)
at sun.plugin2.applet.Applet2Manager.runOnEDT(Applet2Manager.java:3176)
at sun.plugin2.applet.Applet2Manager.access$3600(Applet2Manager.java:87)
at sun.plugin2.applet.Applet2Manager$AppletExecutionRunnable.run(Applet2Manager.java:1454)
at java.lang.Thread.run(Thread.java:619)
Caused by: java.lang.NullPointerException
at ni.d(Unknown Source)
at prophet.chart.JavaChart.setSize(Unknown Source)
at sun.plugin2.applet.Applet2Manager$AppletStubImpl$1.run(Applet2Manager.java:2371)
at sun.plugin2.applet.Applet2Manager$AppletStubImpl.appletResize(Applet2Manager.java:2377)
at java.applet.Applet.resize(Applet.java:201)
at java.applet.Applet.resize(Applet.java:212)
at sun.plugin2.applet.Applet2Manager$AppletExecutionRunnable$1.run(Applet2Manager.java:1466)
at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:199)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:597)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:273)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:183)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:173)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:168)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:160)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:121)

Unfortunately it looks like there is quite a lot of applet code involved and tracking down this problem from our side will require decompiling the applet and lots of analysis of its bytecodes. It would be much simpler to have the customer diagnose the failure in their un-obfuscated code and tell us what the compatibility issue in the new plug-in appears to be.

Note also that there does not appear to be a widespread compatibility problem here; this appears to be an isolated incident.