SASL implementation for PircBotX. Requires the following patch to the bot library: http://code.google.com/p/pircbotx/issues/detail?id=97

SASL.java

public class SASL extends ListenerAdapter {
    String user = "user"; // Change accordingly!
    String password = "password"; // Change accordingly!
    
    boolean connected = false;

    @Override
    public void onMotd(MotdEvent event) throws Exception {
        connected = true;
    }
    
    /**
     * Tokenize IRC raw input into it's components, keeping the
     * 'sender' and 'message' fields intact.
     * @param input A string in the format [:]item [item] ... [:item [item] ...]
     * @return List of strings.
     */
    private static List<String> tokenize(String input) {
        List<String> retn = new ArrayList<String>();
        
        if (input == null || input.length() == 0)
            return retn;
        
        String temp = input;
        
        while (temp.contains(" ")) {
            if (temp.startsWith(":") && retn.size() > 0) {
                retn.add(temp.substring(1));
                
                return retn;
            }
            
            String[] split = temp.split(" ", 2);
            retn.add(split[0]);
            
            if (split.length > 1)
                temp = split[1];
        }
        
        return retn;
    }
    
    @Override
    public void onSocketConnect(SocketConnectEvent event) throws Exception {
        event.respond("CAP LS");
        connected = false;
    }
    
    @Override
    public void onUnknown(UnknownEvent event) throws Exception {
        if (connected)
            return;
        
        String line = event.getLine(); // :Sender CAP MyNick CMD [:More here]
        List<String> args = tokenize(line); // [:Sender, CAP, MyNick, CMD, More here]
        
        if (args.size() >= 1) { 
            if (args.get(0).startsWith(":"))
                args.remove(0); // Sender
            
            String response = args.remove(0); // "CAP"
            if (response.equalsIgnoreCase("CAP")) {
                if (args.size() >= 3) {
                    args.remove(0); // "MyNick"

                    String cmd = args.remove(0); // "CMD"
                    if (cmd.equalsIgnoreCase("NAK"))
                        event.respond("CAP END");
                    
                    else if (cmd.equalsIgnoreCase("LS")) {
                        List<String> caps = Arrays.asList(args.get(0).split(" ")); // [More, here]

                        if (caps.contains("sasl"))
                            event.respond("CAP REQ :sasl");
                        else
                            event.respond("CAP END");
                        
                    } else if (cmd.equalsIgnoreCase("ACK")) {
                        List<String> caps = Arrays.asList(args.get(0).split(" ")); // [More, here]

                        if (caps.contains("sasl"))
                            event.respond("AUTHENTICATE PLAIN");
                    }
                }
                
            } else if (response.equalsIgnoreCase("AUTHENTICATE")) {
                Base64 test = new Base64();
                byte[] out = test.encode((user + '\0' + user + '\0' + password).getBytes("UTF-8"));
                
                event.respond("AUTHENTICATE " +  new String(out));
            }
        }
    }

    @Override
    public void onServerResponse(ServerResponseEvent event) throws Exception {
        if (event.getCode() == 903)
            event.respond("CAP END");
            
        else if (event.getCode() == 904 || event.getCode() == 905) {
            // SASL auth failed.
            // Respond accordingly here...
        }
    }
}