FULL PRODUCT VERSION :
java version "1.6.0_32"
Java(TM) SE Runtime Environment (build 1.6.0_32-b05)
Java HotSpot(TM) 64-Bit Server VM (build 20.7-b02, mixed mode)

java version "1.7.0_04"
Java(TM) SE Runtime Environment (build 1.7.0_04-b22)
Java HotSpot(TM) 64-Bit Server VM (build 23.0-b21, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.1.7601]

A DESCRIPTION OF THE PROBLEM :
In a program I open a ServerSocket on port 7777 when start this program at the same time again I get a BindException as expected. This happens when I use Java 6 or Java 7. But when I use for Java 6 first to start my program and at the same time I start the same program with Java 7 (or first Java 6 and second Java 7) I don't get a BindException. When I start a client program the first started 'server' handles the incoming request. But when I close the first 'server' and I start the client again the second 'server' handles the incoming request.

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
-Windows 7 64 bit
-Open CMD and start test program with Java 6 <location jre6>\bin\java test.ServerSocketExample
-Open CMD and start test program with Java 7 <location jre7>\bin\java test.ServerSocketExample

Does not matter if you start the program first with Java 6 or Java 7.


EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Output of first program
Waiting for client connection on port: 7777

Output of second program
java.net.BindException: Address already in use: JVM_Bind
        at java.net.DualStackPlainSocketImpl.bind0(Native Method)
        at java.net.DualStackPlainSocketImpl.socketBind(Unknown Source)
        at java.net.AbstractPlainSocketImpl.bind(Unknown Source)
        at java.net.PlainSocketImpl.bind(Unknown Source)
        at java.net.ServerSocket.bind(Unknown Source)
        at java.net.ServerSocket.<init>(Unknown Source)
        at java.net.ServerSocket.<init>(Unknown Source)
        at test.ServerSocketExample.<init>(ServerSocketExample.java:13)
        at test.ServerSocketExample.main(ServerSocketExample.java:34)
Waiting for client connection on port: 7777
Exception in thread "main" java.lang.NullPointerException
        at test.ServerSocketExample.handleConnection(ServerSocketExample.java:24)
        at test.ServerSocketExample.main(ServerSocketExample.java:35)
ACTUAL -
Output of first program
Waiting for client connection on port: 7777

Output of second program
Waiting for client connection on port: 7777

netstat -a -n

Active Connections

  Proto Local Address Foreign Address State
  TCP 0.0.0.0:135 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:445 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:1098 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:1099 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:1433 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:1521 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:2099 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:2484 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:3389 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:3528 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:3873 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:4160 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:4444 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:4446 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:4457 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:6002 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:7001 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:7002 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:7777 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:7777 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8080 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8081 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8083 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8085 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8086 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8087 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8088 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8181 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:8501 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:9535 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:9593 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:9594 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:9595 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:33354 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:37204 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:44888 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49152 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49153 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49154 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49214 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49217 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49233 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49234 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49236 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49387 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49388 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49399 0.0.0.0:0 LISTENING
  TCP 0.0.0.0:49404 0.0.0.0:0 LISTENING
  TCP 10.4.16.101:139 0.0.0.0:0 LISTENING
  TCP 10.4.16.101:1098 10.4.16.101:49397 ESTABLISHED
  TCP 10.4.16.101:3389 10.4.24.4:54862 ESTABLISHED
  TCP 10.4.16.101:8086 10.4.16.101:51915 FIN_WAIT_2
  TCP 10.4.16.101:8501 10.4.16.101:49398 ESTABLISHED
  TCP 10.4.16.101:49214 10.4.16.101:51916 TIME_WAIT
  TCP 10.4.16.101:49397 10.4.16.101:1098 ESTABLISHED
  TCP 10.4.16.101:49398 10.4.16.101:8501 ESTABLISHED
  TCP 10.4.16.101:50160 10.1.8.101:445 ESTABLISHED
  TCP 10.4.16.101:51912 10.4.16.101:1098 TIME_WAIT
  TCP 10.4.16.101:51913 10.4.16.101:49388 TIME_WAIT
  TCP 10.4.16.101:51914 10.4.16.101:1098 TIME_WAIT
  TCP 10.4.16.101:51915 10.4.16.101:8086 CLOSE_WAIT
  TCP 127.0.0.1:1434 0.0.0.0:0 LISTENING
  TCP 127.0.0.1:6999 0.0.0.0:0 LISTENING
  TCP 127.0.0.1:9535 127.0.0.1:50034 ESTABLISHED
  TCP 127.0.0.1:9592 0.0.0.0:0 LISTENING
  TCP 127.0.0.1:21584 0.0.0.0:0 LISTENING
  TCP 127.0.0.1:49203 0.0.0.0:0 LISTENING
  TCP 127.0.0.1:49204 0.0.0.0:0 LISTENING
  TCP 127.0.0.1:49222 0.0.0.0:0 LISTENING
  TCP 127.0.0.1:50034 127.0.0.1:9535 ESTABLISHED
  TCP 127.0.0.1:51917 127.0.0.1:53001 TIME_WAIT
  TCP 127.0.0.1:53001 0.0.0.0:0 LISTENING
  TCP [::]:135 [::]:0 LISTENING
  TCP [::]:445 [::]:0 LISTENING
  TCP [::]:1098 [::]:0 LISTENING
  TCP [::]:1099 [::]:0 LISTENING
  TCP [::]:1433 [::]:0 LISTENING
  TCP [::]:2099 [::]:0 LISTENING
  TCP [::]:3389 [::]:0 LISTENING
  TCP [::]:3528 [::]:0 LISTENING
  TCP [::]:3873 [::]:0 LISTENING
  TCP [::]:4160 [::]:0 LISTENING
  TCP [::]:4444 [::]:0 LISTENING
  TCP [::]:4446 [::]:0 LISTENING
  TCP [::]:4457 [::]:0 LISTENING
  TCP [::]:7777 [::]:0 LISTENING
  TCP [::]:7777 [::]:0 LISTENING
  TCP [::]:8081 [::]:0 LISTENING
  TCP [::]:8083 [::]:0 LISTENING
  TCP [::]:8085 [::]:0 LISTENING
  TCP [::]:8086 [::]:0 LISTENING
  TCP [::]:8087 [::]:0 LISTENING
  TCP [::]:8088 [::]:0 LISTENING
  TCP [::]:8181 [::]:0 LISTENING
  TCP [::]:8501 [::]:0 LISTENING
  TCP [::]:37204 [::]:0 LISTENING
  TCP [::]:44888 [::]:0 LISTENING
  TCP [::]:49152 [::]:0 LISTENING
  TCP [::]:49153 [::]:0 LISTENING
  TCP [::]:49154 [::]:0 LISTENING
  TCP [::]:49214 [::]:0 LISTENING
  TCP [::]:49217 [::]:0 LISTENING
  TCP [::]:49233 [::]:0 LISTENING
  TCP [::]:49234 [::]:0 LISTENING
  TCP [::]:49236 [::]:0 LISTENING
  TCP [::]:49387 [::]:0 LISTENING
  TCP [::]:49388 [::]:0 LISTENING
  TCP [::]:49399 [::]:0 LISTENING
  TCP [::]:49404 [::]:0 LISTENING
  TCP [::1]:1434 [::]:0 LISTENING
  TCP [::1]:6999 [::]:0 LISTENING
  UDP 0.0.0.0:123 *:*
  UDP 0.0.0.0:500 *:*
  UDP 0.0.0.0:1434 *:*
  UDP 0.0.0.0:4160 *:*
  UDP 0.0.0.0:4160 *:*
  UDP 0.0.0.0:4500 *:*
  UDP 0.0.0.0:5355 *:*
  UDP 0.0.0.0:7001 *:*
  UDP 0.0.0.0:9595 *:*
  UDP 0.0.0.0:33354 *:*
  UDP 0.0.0.0:33355 *:*
  UDP 0.0.0.0:38293 *:*
  UDP 0.0.0.0:55932 *:*
  UDP 10.4.16.101:123 *:*
  UDP 10.4.16.101:137 *:*
  UDP 10.4.16.101:138 *:*
  UDP 10.4.16.101:6001 *:*
  UDP 127.0.0.1:123 *:*
  UDP 127.0.0.1:6001 *:*
  UDP 127.0.0.1:53399 *:*
  UDP 127.0.0.1:58903 *:*
  UDP 127.0.0.1:60317 *:*
  UDP [::]:500 *:*
  UDP [::]:1434 *:*
  UDP [::]:4160 *:*
  UDP [::]:4160 *:*
  UDP [::]:4500 *:*
  UDP [::]:55932 *:*

REPRODUCIBILITY :
This bug can be reproduced always.

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

import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
 
public class ServerSocketExample {
    private ServerSocket server;
    private int port = 7777;
 
    public ServerSocketExample() {
        try {
            server = new ServerSocket(port);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
 
    public void handleConnection() {
        System.out.println("Waiting for client connection on port: " + port);
 
        while (true) {
            try {
                Socket socket = server.accept();
                socket.close();
                //new ConnectionHandler(socket);
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
    
    public static void main(String[] args) {
        ServerSocketExample example = new ServerSocketExample();
        example.handleConnection();
    }
---------- END SOURCE ----------