WARNING: NPC 12031 class not found
java.lang.ClassCastException: net.sf.l2j.gameserver.ai.L2SiegeGuardAI
        at net.sf.l2j.gameserver.model.L2Attackable.OnSpawn(L2Attackable.java:1639)
        at net.sf.l2j.gameserver.model.L2Spawn.intializeNpcInstance(L2Spawn.java:476)
        at net.sf.l2j.gameserver.model.L2Spawn.doSpawn(L2Spawn.java:411)
        at net.sf.l2j.gameserver.model.L2Spawn.init(L2Spawn.java:333)
        at net.sf.l2j.gameserver.instancemanager.SiegeGuardManager.spawnSiegeGuard(SiegeGuardManager.java:127)
        at net.sf.l2j.gameserver.model.entity.Siege.spawnSiegeGuard(Siege.java:1125)
        at net.sf.l2j.gameserver.model.entity.Siege.startSiege(Siege.java:351)
        at net.sf.l2j.gameserver.handler.admincommandhandlers.AdminSiege.useAdminCommand(AdminSiege.java:187)
        at net.sf.l2j.gameserver.clientpackets.RequestBypassToServer.runImpl(RequestBypassToServer.java:80)
        at net.sf.l2j.gameserver.clientpackets.ClientBasePacket.run(ClientBasePacket.java:59)
        at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:650)
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:675)
        at java.lang.Thread.run(Thread.java:595)