FULL PRODUCT VERSION :
java version "1.4.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build 1.4.1_01-b01)
Java HotSpot(TM) Client VM (build 1.4.1_01-b01, mixed mode)


FULL OPERATING SYSTEM VERSION :  customer  Windows 2000
[Version 5.00.2195]


A DESCRIPTION OF THE PROBLEM :
Given a synchronized code block within a method that is
compiled using JDK 1.4.x  an attempt to execute the code
using JDK 1.2.x results in the following run-time error
message "Exception in thread "main"
java.lang.IllegalMonitorStateException: current thre
d not owner"



REGRESSION.  Last worked in version 1.3.1

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
1. Compile java source code with synchronized code block in
a method using JDK 1.4.x
2. Run code using JDK 1.4.x  Code runs fine.
3. Run code using JDK 1.2.x  Run-time error is generated

EXPECTED VERSUS ACTUAL BEHAVIOR :
---BEGIN JDK 1.4.1 ----

As compiled and run with JDK 1.4.1

C:\testsynch>java -version
java version "1.4.1_01"
Java(TM) 2 Runtime Environment, Standard Edition (build
1.4.1_01-b01)
Java HotSpot(TM) Client VM (build 1.4.1_01-b01, mixed mode)

C:\testsynch>javac -classpath .; Test.java

C:\testsynch>java -cp .; Test
This is a test

C:\testsynch>

--- END JDK 1.4.1 ---


--- BEGIN JDK 1.2.2 ----

Class compiled using JDK 1.4.1 and run with JDK 1.2.2

C:\testsynch>java -version
java version "1.2.2"
Classic VM (build JDK-1.2.2_007, native threads, symcjit)

C:\testsynch>java -cp .; Test
This is a test
Exception in thread "main"
java.lang.IllegalMonitorStateException: current thre
d not owner
        at Test.main(Test.java:5)

C:\testsynch>

--- END JDK 1.2.2 ---


ERROR MESSAGES/STACK TRACES THAT OCCUR :
Exception in thread "main" java.lang.IllegalMonitorStateException: current thre
d not owner
        at Test.main(Test.java:5)


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
public class Test {

public static void main(String[] args) {
  Test t = new Test();
  t.execute();
}

public void execute() {
  synchronized(this) {
    System.out.println("This is a test");
  }
}

}
---------- END SOURCE ----------

CUSTOMER WORKAROUND :
No known workaround.  As a developer of thread-safe
components I use synchronized code blocks frequently.
Unfortunately this prevents me from supporting JDK 1.2.x
end users when compiling with JDK 1.4.x

Release Regression From : 1.4.1
The above release value was the last known release where this 
bug was known to work. Since then there has been a regression.

(Review ID: 166702) 
======================================================================

Compile in JDK 1.2.2 and run on all JDK's from 1.2.2 and up.
  xxxxx@xxxxx   2002-11-11

Alternative, install hotspot 2.0 vm in jdk 1.2.2_014 and all should be fine.
  xxxxx@xxxxx   2002-11-11

Note: any fix would have to be in the JDK 1.2.2 vm which would require a
VM download for your customers - so you can choose to either require
your customers to download the hotspot 2.0 vm or build on the
earliest release you want to support.

This appears to be a bug in the 1.2.2 windows runtime.  The compiler-generated
code appears to be correct.

  xxxxx@xxxxx   2002-11-08

Running with -classic VM is the issue here.  After installing hotspot 2.0 into
JDK 1.2.2_14 the program ran fine when compiled with JDK 1.4.2 and run on
JDK 1.2.2_14


  xxxxx@xxxxx   2002-11-11


  xxxxx@xxxxx   2002-11-26

Appears to be a bug with the 1.2.2 symcjit. If I run javac on 1.4.2,
and then run java_g on 1.2.2_014 I get the following message:
  " Warning: JIT compiler "symcjit" not found. Will use interpreter

And the test passes.

Running with 1.2.2_014 java gets the exception. This appears to
be a bug in the JIT compiler "symcjit" on 1.2.2.

Alternatively it could be a difference between the synchronization
path between debug and product.