why this error? i need help

[icemanrj]

Client: [Character: tes[268491989] - Account: test - IP: 154.96.245.33] - Failed running: [C] 03 EnterWorld - L2J Server Version: 3 - DP Revision: 3 ; javolution.util.FastSet.shared()Ljavolution/util/FastSet;
java.lang.NoSuchMethodError: javolution.util.FastSet.shared()Ljavolution/util/FastSet;
at com.l2jserver.gameserver.model.actor.L2Character.getAttackByList(L2Character.java:2266)
at com.l2jserver.gameserver.ai.L2AttackableAI.thinkActive(L2AttackableAI.java:510)
at com.l2jserver.gameserver.ai.L2AttackableAI.onEvtThink(L2AttackableAI.java:2321)
at com.l2jserver.gameserver.ai.L2CharacterAI.onIntentionActive(L2CharacterAI.java:175)
at com.l2jserver.gameserver.ai.L2AttackableAI.onIntentionActive(L2AttackableAI.java:2447)
at com.l2jserver.gameserver.ai.AbstractAI.setIntention(AbstractAI.java:302)
at com.l2jserver.gameserver.ai.AbstractAI.setIntention(AbstractAI.java:248)
at com.l2jserver.gameserver.model.actor.knownlist.MonsterKnownList.addKnownObject(MonsterKnownList.java:41)
at com.l2jserver.gameserver.model.L2World.addVisibleObject(L2World.java:375)
at com.l2jserver.gameserver.model.L2Object.spawnMe(L2Object.java:502)
at com.l2jserver.gameserver.network.clientpackets.EnterWorld.runImpl(EnterWorld.java:344)
at com.l2jserver.gameserver.network.clientpackets.L2GameClientPacket.run(L2GameClientPacket.java:92)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:619)


in my server loard i see no errors

[JIV]

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