IE hangs as one applet unloads and another applet starts. It looks to me
as if the plugin is deadlocked while trying to load classes at the same
time it attempts to kill the threads associated with the previous (dumped) applet. The applet that is being dumped is attempting to deserialize an
object at the time of the hang.

Unfortunately, for this problem, I cannot provide a simpler test case. So I
am sending along three files, jdb_output, and a failure plugin trace
(plugin131_hangs) and a success plugin trace (plugin131_works).

I have been able to reproduce the problem with IE 5.0 and 5.5 and java plugin,
1.3.0-C, 1.3.0_01, 1.3.0_02, and 1.3.1 RC1. I have not had a chance to try
this with Netscape.