class file1:
package net.sf.l2j.gameserver;

import java.io.FileReader;
import java.util.ArrayList;
import java.util.logging.Logger;

import net.sf.l2j.Config;
import net.sf.l2j.fscript.L2JAIExtension;

public class AIScript
{
    private static Logger _log = Logger.getLogger(AIScript.class.getName());
    private static L2JAIExtension fs;
    private static AIScript _instance;
    private static final int AIVersion=100;
    public boolean _debug;

    public AIScript()
    {
        fs = new L2JAIExtension();
        reload();
    }
    
    public static AIScript getInstance()
    {
        if(_instance == null)
            _instance = new AIScript();
        return _instance;
    }
    
    public void reload()
    {
        try
        {
            _log.info("AIScript: loading script...");
            fs.reset();
            fs.load( new FileReader(Config.DATAPACK_ROOT+"/data/ai.obj"));
            _log.info("AIScript: executing...");
            fs.run();
            _debug = false;
            
            if((Integer)(fs.getScriptVar("L2JAIVersion")) != AIVersion)
            {
                _log.warning("Invalid ai.obj version!");
            }
            
            if((Integer)(fs.getScriptVar("L2JAIDebug")) == 1)
            {
                _log.info("AIScript: debugging enabled");
                _debug = true;
            }
        }
        catch(Exception e)
        {
            _log.warning("Error loading ai.obj: "+e);
            e.printStackTrace();
        }
    }
    
    /**
     * Handle interrupt issued by AbstractAI onEvent handler
     * @param handler - handler name
     * @param params - params array
     * first param are always reference to 'self' - caller ObjectID
     * @return - ai handler output value, <b>CAN BE NULL</b>
     */
    public Object handleInterrupt(String handler,ArrayList params)
    { 
        Object result = null;
        
        if(params == null)
        {
            params = new ArrayList<Integer>();
        }
        
        try
        {
            result = fs.callScriptFunction(handler,params);
        }
        catch(Exception e)
        {
            _log.warning("AIScript: ERROR WHILE HANDLING INTERRUPT! "+e);
        }

        return result;
    }
}


class file2:

package net.sf.l2j.fscript;

import java.util.ArrayList;

import net.sf.l2j.gameserver.AIScript;
import net.sf.l2j.gameserver.model.L2Character;
import net.sf.l2j.gameserver.model.L2NpcInstance;
import net.sf.l2j.gameserver.model.L2PcInstance;
import net.sf.l2j.gameserver.model.L2World;
import net.sf.l2j.gameserver.serverpackets.CreatureSay;

public class L2JAIExtension extends FScript
{
    private Object files[];
    
    /**Constructor*/
    public L2JAIExtension()
    {
        super();
        files=new Object[25];
    }
    
    public Object callFunction(String name,ArrayList param) throws FSException
    {
        if (name.equals("dbgprint"))
        {
            if(AIScript.getInstance()._debug)
            {
                String s="";
                for(int n=0;n<param.size();n++)
                {
                    s=s+param.get(n);
                }
                System.out.println(s);
            }
        }
        else if(name.equals("GetPlayerName"))
        {
            Integer objectId = (Integer)param.get(0);
            L2PcInstance player = (L2PcInstance)L2World.getInstance().findObject(objectId);
            if(player != null)
                return player.getName();
        }
        else if(name.equals("Say"))
        {
            Integer objectId = (Integer)param.get(0);
            String s="";
            for(int n=1;n<param.size();n++)
            {
                s=s+param.get(n);
            }
            
            L2Character npc = (L2Character)L2World.getInstance().findObject(objectId);
            if(npc != null)
                npc.broadcastPacket(new CreatureSay(objectId,0,npc.getName(),s));
        }
        else if(name.equals("GetHP"))
        {
            Integer objectId = (Integer)param.get(0);
            L2Character npc = (L2Character)L2World.getInstance().findObject(objectId);
                if(npc != null)
                    return npc.getCurrentHp();
        }
        else if(name.equals("GetMP"))
        {
            Integer objectId = (Integer)param.get(0);
            L2Character npc = (L2Character)L2World.getInstance().findObject(objectId);
            if(npc != null)
                return npc.getCurrentMp();
        }
        else if(name.equals("GetNpcClass"))
        {
            Integer objectId = (Integer)param.get(0);
            L2NpcInstance npc = (L2NpcInstance)L2World.getInstance().findObject(objectId);
            if(npc != null)
                return npc.getTemplate().type;
        }
        else if(name.equals("GetNpcFaction"))
        {
            Integer objectId = (Integer)param.get(0);
            L2NpcInstance npc = (L2NpcInstance)L2World.getInstance().findObject(objectId);
            if(npc != null)
                return npc.getTemplate().factionId;
        }
        else
        {
            super.callFunction(name,param);
        }

        return new Integer(0);
    }
}


patch:
Index: C:/eclipse-31m7/workspace/c4/L2_GameServer/java/net/sf/l2j/gameserver/GameServer.java
===================================================================
--- C:/eclipse-31m7/workspace/c4/L2_GameServer/java/net/sf/l2j/gameserver/GameServer.java	(revision 1250)
+++ C:/eclipse-31m7/workspace/c4/L2_GameServer/java/net/sf/l2j/gameserver/GameServer.java	(working copy)
@@ -30,6 +30,7 @@
 import net.sf.l2j.gameserver.handler.SkillHandler;
 import net.sf.l2j.gameserver.handler.UserCommandHandler;
 import net.sf.l2j.gameserver.handler.VoicedCommandHandler;
+import net.sf.l2j.gameserver.handler.admincommandhandlers.AdminAI;
 import net.sf.l2j.gameserver.handler.admincommandhandlers.AdminAdmin;
 import net.sf.l2j.gameserver.handler.admincommandhandlers.AdminAnnouncements;
 import net.sf.l2j.gameserver.handler.admincommandhandlers.AdminBan;
@@ -409,6 +410,7 @@
         _adminCommandHandler.registerAdminCommandHandler(new AdminMammon());
         _adminCommandHandler.registerAdminCommandHandler(new AdminUnblockIp());
         _adminCommandHandler.registerAdminCommandHandler(new AdminPledge());
+        _adminCommandHandler.registerAdminCommandHandler(new AdminAI());
 
         //_adminCommandHandler.registerAdminCommandHandler(new AdminRadar());
         _log.config("AdminCommandHandler: Loaded " + _adminCommandHandler.size() + " handlers.");
Index: C:/eclipse-31m7/workspace/c4/L2_GameServer/java/net/sf/l2j/gameserver/ai/L2AttackableAI.java
===================================================================
--- C:/eclipse-31m7/workspace/c4/L2_GameServer/java/net/sf/l2j/gameserver/ai/L2AttackableAI.java	(revision 1250)
+++ C:/eclipse-31m7/workspace/c4/L2_GameServer/java/net/sf/l2j/gameserver/ai/L2AttackableAI.java	(working copy)
@@ -22,11 +22,13 @@
 import static net.sf.l2j.gameserver.ai.CtrlIntention.AI_INTENTION_ATTACK;
 import static net.sf.l2j.gameserver.ai.CtrlIntention.AI_INTENTION_IDLE;
 
+import java.util.ArrayList;
 import java.util.Random;
 import java.util.concurrent.Future;
 import java.util.logging.Logger;
 
 import net.sf.l2j.Config;
+import net.sf.l2j.gameserver.AIScript;
 import net.sf.l2j.gameserver.ClientScheduler;
 import net.sf.l2j.gameserver.GameTimeController;
 import net.sf.l2j.gameserver.Territory;
@@ -94,7 +96,6 @@
 	{
 		// Launch actions corresponding to the Event Think
 		onEvtThink();
-		
 	}
 	
 	/**
@@ -676,6 +677,11 @@
 	 */
 	protected void onEvtAttacked(L2Character attacker)
 	{
+        ArrayList<Object> args = new ArrayList<Object>();
+        args.add(_actor.getObjectId());
+        args.add(attacker.getObjectId());
+        AIScript.getInstance().handleInterrupt("onEventAttacked",args);
+
 		// Calculate the attack timeout
 		_attack_timeout = MAX_ATTACK_TIMEOUT + GameTimeController.getGameTicks();
 		

admin handler:
package net.sf.l2j.gameserver.handler.admincommandhandlers;

import net.sf.l2j.gameserver.AIScript;
import net.sf.l2j.gameserver.handler.IAdminCommandHandler;
import net.sf.l2j.gameserver.model.L2PcInstance;

public class AdminAI implements IAdminCommandHandler
{
    private static String[] _adminCommands = {"admin_ai_reload"};
    
    public boolean useAdminCommand(String command, L2PcInstance activeChar)
    {
        if (command.equals("admin_ai_reload"))
        {
            AIScript.getInstance().reload();
        }
        
        return true;
    }
    
    public String[] getAdminCommandList()
    {
        return _adminCommands;
    }
}

ai.obj:
int L2JAIVersion=100
int L2JAIDebug=1

func onIdle(int objectId)
  dbgprint("idle")
endfunc

##########################################
#       real events goes here
##########################################

func onEventThink(int self)
    dbgprint("handling event: Think ")
endfunc


func onEventAttacked(int self, int attacker)
    dbgprint("handling event: Attacked, by oid: "+attacker)
    string playerName=getPlayerName(attacker)
    #dbgprint(playerName)
    double currentHp=GetHP(self)
    Say(self,"OMFG! I'm attacked by "+playerName+"! My hp are: "+currentHp)
    string class=GetNpcClass(self)
    dbgprint("class: "+class)
endfunc

func onEventAggression(int self, int target, int value)
    dbgprint("handling event: Aggression")
endfunc

func onEventReady(int self)
    dbgprint("handling event: ready")
endfunc

func onEventArrived(int self)
    dbgprint("handling event: Arrived")
endfunc

func onEventDead(int self)
    dbgprint("handling event: Dead")
endfunc