java.net.BindException：在 Mac OSX 上创建 ServerSocket 时权限被拒绝

我试图在Mac中运行一个带有eclipse的Java套接字，但它不起作用。我得到这个错误：

Exception in thread "main" java.net.BindException: Permission denied

    at java.net.PlainSocketImpl.socketBind(Native Method)
    at java.net.PlainSocketImpl.socketBind(PlainSocketImpl.java:521)
    at java.net.PlainSocketImpl.bind(PlainSocketImpl.java:414)
    at java.net.ServerSocket.bind(ServerSocket.java:326)
    at java.net.ServerSocket.<init>(ServerSocket.java:192)
    at java.net.ServerSocket.<init>(ServerSocket.java:104)
    at server.MessageServer.main(MessageServer.java:11)

我怎样才能让它运行？

package server; //ChatServer 
import java.io.*; 
import java.net.*; 

public class MessageServer { 

public static void main (String args[]) throws IOException { 
    int port = 100; 
    ServerSocket server = new ServerSocket (port); 
    System.out.println("Server is started!"); 

    while (true) { 
        Socket client = server.accept (); 
        System.out.println ("Accepted from " + client.getInetAddress ()); 
        MessageHandler handler = new MessageHandler (client); 
        handler.start(); 
        } 
    } 
}