The following code results often hangs up in mixed mode (both Client and Server) on Solaris 10 x86:

class Thr extends Thread {
        int thr_id;

        Thr(int thr_id)
        {
                this.thr_id = thr_id;
        }

        public synchronized void run () {

                try
                {
                        sleep(1000);
                }
                catch (Exception e) { }
        }
}

public class ThreadStopTest2 implements Test {

        public void run(String[] args, PrintStream log, PrintStream out) {

                boolean be = false;

                Thr t1 = new Thr(1);
                t1.start();

                Thr t2 = new Thr(2);
                t2.start();

                try {
                        t1.stop(o);
                }
                catch (Exception e) {
                        System.out.println("FAILED");
                } catch (Error err) {
                        System.out.println(err.toString());
                }

                try {
                        t1.join();
                }
                catch (InterruptedException e) { be=true; }

                if (be || t1.isAlive())
                        System.out.println("FAILED");
        }

        public static void main (String args[])
        {
                ThreadStopTest2 test = new ThreadStopTest2();
                test.run(args, System.err, System.out);
        }
}

Below is a thread dump obtained with Ctrl-\:

^\2006-03-14 05:14:07
Full thread dump Java HotSpot(TM) Client VM (20060310062435.dcubed.service_hs_b76_merge mixed mode):

"Attach Listener" daemon prio=10 tid=0x08452800 nid=0xc runnable [0x00000000..0xc7962a90]
   java.lang.Thread.State: RUNNABLE

"Thread-0" prio=10 tid=0x08452000 nid=0xa waiting for monitor entry [0xc79b4000..0xc79b49f0]
   java.lang.Thread.State: BLOCKED (on object monitor)
        at runtime.threads.ThreadStopTest2.Thr.run(ThreadStopTest2.java:26)
        - waiting to lock <0xbfd84610> (a runtime.threads.ThreadStopTest2.Thr)

"Low Memory Detector" daemon prio=10 tid=0x0817e800 nid=0x8 runnable [0x00000000..0x00000000]
   java.lang.Thread.State: RUNNABLE

"CompilerThread0" daemon prio=10 tid=0x0817d400 nid=0x7 waiting on condition [0x00000000..0xc7aa7488]
   java.lang.Thread.State: RUNNABLE

"Signal Dispatcher" daemon prio=10 tid=0x0817c400 nid=0x6 waiting on condition [0x00000000..0xc7af9820]
   java.lang.Thread.State: RUNNABLE

"Finalizer" daemon prio=10 tid=0x08162800 nid=0x5 in Object.wait() [0xc7b4b000..0xc7b4bc70]
   java.lang.Thread.State: WAITING (on object monitor)
        at java.lang.Object.wait(Native Method)
        - waiting on <0xbfd46b30> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:116)
        - locked <0xbfd46b30> (a java.lang.ref.ReferenceQueue$Lock)
        at java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:132)
        at java.lang.ref.Finalizer$FinalizerThread.run(Finalizer.java:159)

"Reference Handler" daemon prio=10 tid=0x08161800 nid=0x4 in Object.wait() [0xc7b9d000..0xc7b9daf0]
   java.lang.Thread.State: WAITING (on object monitor)
        at java.lang.Object.wait(Native Method)
        - waiting on <0xbfd46920> (a java.lang.ref.Reference$Lock)
        at java.lang.Object.wait(Object.java:484)
        at java.lang.ref.Reference$ReferenceHandler.run(Reference.java:116)
        - locked <0xbfd46920> (a java.lang.ref.Reference$Lock)

"main" prio=10 tid=0x08070c00 nid=0x2 in Object.wait() [0xc9ffd000..0xc9ffdd58]
   java.lang.Thread.State: WAITING (on object monitor)
        at java.lang.Object.wait(Native Method)
        - waiting on <0xbfd84610> (a runtime.threads.ThreadStopTest2.Thr)
        at java.lang.Thread.join(Thread.java:1155)
        - locked <0xbfd84610> (a runtime.threads.ThreadStopTest2.Thr)
        at java.lang.Thread.join(Thread.java:1208)
        at runtime.threads.ThreadStopTest2.ThreadStopTest2.run(ThreadStopTest2.java:55)
        at runtime.threads.ThreadStopTest2.ThreadStopTest2.main(ThreadStopTest2.java:68)

"VM Thread" prio=10 tid=0x0815e400 nid=0x3 runnable

"VM Periodic Task Thread" prio=10 tid=0x08180800 nid=0x9 waiting on condition

JNI global references: 778

Heap
 def new generation total 960K, used 137K [0xbf800000, 0xbf900000, 0xbfce0000)
  eden space 896K, 8% used [0xbf800000, 0xbf812520, 0xbf8e0000)
  from space 64K, 100% used [0xbf8f0000, 0xbf900000, 0xbf900000)
  to space 64K, 0% used [0xbf8e0000, 0xbf8e0000, 0xbf8f0000)
 tenured generation total 4096K, used 1431K [0xbfce0000, 0xc00e0000, 0xc3800000)
   the space 4096K, 34% used [0xbfce0000, 0xbfe45e80, 0xbfe46000, 0xc00e0000)
 compacting perm gen total 12288K, used 6161K [0xc3800000, 0xc4400000, 0xc7800000)
   the space 12288K, 50% used [0xc3800000, 0xc3e04710, 0xc3e04800, 0xc4400000)
No shared spaces configured.