I've been creating a java web start swing/jython app for awhile now, and last week I ran into quite an odd problem.  I have yet to track down its exact source, but I do know the things that changed right before the problem occurred.  Let me describe the problem first:
After signing the jar files used by the application and deploying it to the server, the application works and is downloadable to the client, and will start execution.  However, after a point, swing JInternalFrames I create fail to ever appear.  The interpreted version of the app runs fine without this problem.  The problem appears after only three JInternalFrames have displayed.  No tracebacks occur that I can find, and the (jython) threads used to display and update these invisible JInternalFrames are running (I have a logging window that they each write to, and can see output from each thread).
-  I'm running jython 2.1, sun jdk 1.4.1_02, and utilize jfreechart (http://www.jfree.org/jfreechart).
-  The problem occurs regardless fo what client machine the web start app is run from (I.e., its not just my machine being funky)
-  The problem did not exist prior to the integration of jfreechart, but other code changes were made simultaneously.
       - somewhere during these changes, I did something that made me (later, when I went to make the jar) run into the ProxyMaker problem and was forced to change the -core option of jythonc to use -all instead, thanks to this this list (http://aspn.activestate.com/ASPN/Mail/Message/724323) I was able to find the solution of using -all, but not the reason _why_.  None of my code calls eval or anything similar, so why does my app suddenly need the compile support?
-  Due to the security restrictions put in place on web start apps, I cannot test the app without signing the jars - could my signing of the third-part jfreechart jars have caused this problem? (Until I signed them, I still got security errors: what should I do if I am not to sign third party jars?)
-  how can I trap for exceptions in an eventDispatch thread (or any pure-java thread) from jython?  I can trap and print traceback information for my threads to my logging window, but while runnign the app in interpreted mode I sometimes cause a bug that shows up via a eventDispatch thread exception - how would I trap for this (or other errors) so that I could show the traceback in my own custom logging window?
I have probably left out some important detail somewhere that would make my problem obvious, but I can't even find an instance of this sort of thing being reported.  Even if you don't know the solution to the overall problem, could someone step up and answer some of the sub-questions raised above?
Thank you in advance!
~Jon Franz