J2SE Version (please include all output from java -version flag):
  java version "1.4.1-rc"
  Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1-rc-b16)
  Java HotSpot(TM) Server VM (build 1.4.1-rc-b16, mixed mode)

Does this problem occur on J2SE 1.3 or 1.4? Yes / No (pick one)
  Not sure. It is apparently a threading bug, so might be rare.

Operating System Configuration Information (be specific): Solaris 9
Hardware Configuration Information (be specific): 4x450 Ultra-80
   Works fine on Ultra10 1-cpu machine.
Bug Description: Crash with core file. Sometimes it just hang for 1K classes/threads.

Steps to Reproduce (be specific):
=================================
1) unzip concurrent.zip (Get util.concurrent package from http://gee.cs.oswego.edu - also concurrent.zip attached here).
2) cd concurrent
3) mkdir classes
4) javac -d classes *.java
5) cp misc/* classes/.
6) cd classes
7) javac *.java
8) mkdir EDU/oswego/cs/dl/util/concurrent/misc
9) mv *.class EDU/oswego/cs/dl/util/concurrent/misc/.
10) mv *.java EDU/oswego/cs/dl/util/concurrent/misc/.
11) mv *.html EDU/oswego/cs/dl/util/concurrent/misc/.
12) java -server -Xmx128m EDU.oswego.cs.dl.util.concurrent.misc.SynchronizationTimer
13) Above command should result in an application window launching. Below are steps user
    needs to execute to reproduce issue (also reflected in 'panel-operation.JPG'):
    NOTE: user must set path (PATH env) to a valid java executable variable before launching GUI.
14) In application GUI, click "no classes".
15) Click "waitfreeQueue"
16) Set "128k calls per thread" in combo box
17) Set "1M iterations per barrier" in combo box.
18) Click "start"
19) You should get follwoing hotspot error message:

# HotSpot Virtual Machine Error, Internal Error
# Please report this error at
# http://java.sun.com/cgi-bin/bugreport.cgi
#
# Java VM: Java HotSpot(TM) Server VM (1.4.1-rc-b16 mixed mode)
#
# Error ID: 53484152454432554E54494D450E435050014F 01
#
# Problematic Thread: prio=4 tid=0x5ab228 nid=0x8b4 runnable
#

And a core file been generated.