Java symbol confusion

Hi there,

I started learning myself java a while ago and there's still loads of
concepts and things about the java language i don't know, so i may just
make an arse of myself now...

I use the NetBeans 5.0 IDE to play around with. Sometimes it does
things that I think (from what I've learned about java) that it
shouldn't do. I may just be stupid or something, so could somebody
point out my faults. Here's a piece of code:

import java.net.*;
import java.io.*;

public class Main {

    public static void main(String[] args) {

        try {
        ServerSocket serverSocket = new ServerSocket(56);

        }catch (IOException e) {System.out.println("Daar was kak in die
konneksie...");}

        Socket clientSocket = null;
<<------------------------------------
        clientSocket = serverSocket.accept();
<<------------------------------------
        }
}

Ok that's just part of it. I'm still learning how to do the rest. Ok,
my first problem here is that when the two lines marked with arrows
above is out of the try-catch block, NetBeans tells me it can't find
the symbol serverSocket. On the other hand, when I put the two marked
lines inside of the try-catch block, it works without a problem. Can
someone explain to me why this is happening??

===========WORKING=============
        try {
        ServerSocket serverSocket = new ServerSocket(56);
        Socket clientSocket = null;
        clientSocket = serverSocket.accept();
        }catch (IOException e) {System.out.println("Daar was kak in die
konneksie...");}

===========NOT WORKING=============

        try {
        ServerSocket serverSocket = new ServerSocket(56);
        }catch (IOException e) {System.out.println("Daar was kak in die
konneksie...");}
        Socket clientSocket = null;
        clientSocket = serverSocket.accept();

It says:

C:\Documents and
Settings\Constant\netServer\src\netserver\Main.java:22: cannot find
symbol
symbol : variable serverSocket
location: class Main
        clientSocket = serverSocket.accept();
1 error
BUILD FAILED (total time: 0 seconds)