FULL PRODUCT VERSION :
java version "1.6.0_14"
Java(TM) SE Runtime Environment (build 1.6.0_14-b08)
Java HotSpot(TM) Server VM (build 14.0-b16, mixed mode)

The same behavior is also reproducible on
Linux (32 bit) with 1.6.0_14.

It is further reproducible with 1.7.0-ea (build 1.7.0-ea-b59) on
both Win XP (32 bit) and Linux (32 bit).


FULL OS VERSION :
Microsoft Windows XP [Version 5.1.2600] (SP3)

EXTRA RELEVANT SYSTEM CONFIGURATION :
CPU: Intel T7200 Dual Core @ 2 GHz

A DESCRIPTION OF THE PROBLEM :

Summing all ints from Integer.MIN_VALUE up to Integer.MAX_VALUE - 1 into a long variable gives different results when run in the server VM as opposed to the client VM.

Doing this 10 times gives even 2 different results for the server VM!

This doesn't happen in the client VM or in interpreted (-Xint) mode.

(I checked the behavior for the older server VMs: 1.6.0_12, 1.5.0_17 and 1.4.2_17 - all of them deliver the "expected" result shown below)

THE PROBLEM WAS REPRODUCIBLE WITH -Xint FLAG: No

THE PROBLEM WAS REPRODUCIBLE WITH -server FLAG: Yes

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run the test case (test.TestCase) with the 1.6.0_14 server VM on Windows XP

My command line is: "F:\Develop>F:\Java\sun-jdk1.6.0_14\bin\java -server test.TestCase"

EXPECTED VERSUS ACTUAL BEHAVIOR :
Expected results:

sum: -4294967295
sum: -4294967295
sum: -4294967295
sum: -4294967295
sum: -4294967295
sum: -4294967295
sum: -4294967295
sum: -4294967295
sum: -4294967295
sum: -4294967295

Actual results:

sum: -32212254615
sum: -36507221880
sum: -36507221880
sum: -36507221880
sum: -36507221880
sum: -36507221880
sum: -36507221880
sum: -36507221880
sum: -36507221880
sum: -36507221880

Note, the first output is differs from the rest. All of them seem to be wrong.


REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
package test;

public class TestCase {

	public static void main(String[] args) {
		test();
	}

	private static void test() {
		for (int j = 0; j < 10; ++j) {
			long x = 0;
			for (int i = Integer.MIN_VALUE; i < Integer.MAX_VALUE; ++i) {
				x += i;
			}
			System.out.println("sum: " + x);
		}
	}
}

---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
None (apart from goin back to 1.6.0 Update 12 where this doesn't happen)

Release Regression From : 6u13
The above release value was the last known release where this 
bug was not reproducible. Since then there has been a regression.