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java.lang.AbstractMethodError: redgear.morebackpacks.backpacks.BackpackRedstone.isValidItem(Lnet/minecraft/item/ItemStack;)Z
at forestry.storage.PickupHandlerStorage.onItemPickup(PickupHandlerStorage.java:55)
at forestry.core.EventHandlerCore.handleItemPickup(EventHandlerCore.java:41)
at cpw.mods.fml.common.eventhandler.ASMEventHandler_158_EventHandlerCore_handleItemPickup_EntityItemPickupEvent.invoke(.dynamic)
at cpw.mods.fml.common.eventhandler.ASMEventHandler.invoke(ASMEventHandler.java:54)
at cpw.mods.fml.common.eventhandler.EventBus.post(EventBus.java:138)
at net.minecraft.entity.item.EntityItem.func_70100_b_(EntityItem.java:345)
at net.minecraft.entity.player.EntityPlayer.func_71044_o(EntityPlayer.java:609)
at net.minecraft.entity.player.EntityPlayer.func_70636_d(EntityPlayer.java:600)
at net.minecraft.entity.EntityLivingBase.func_70071_h_(EntityLivingBase.java:1611)
at net.minecraft.entity.player.EntityPlayer.func_70071_h_(EntityPlayer.java:288)
at net.minecraft.entity.player.EntityPlayerMP.func_71127_g(EntityPlayerMP.java:295)
at net.minecraft.network.NetHandlerPlayServer.func_147347_a(NetHandlerPlayServer.java:303)
at net.minecraft.network.play.client.C03PacketPlayer.func_148833_a(SourceFile:137)
at net.minecraft.network.play.client.C03PacketPlayer$C06PacketPlayerPosLook.func_148833_a(SourceFile:20)
at net.minecraft.network.NetworkManager.func_74428_b(NetworkManager.java:212)
at net.minecraft.network.NetworkSystem.func_151269_c(NetworkSystem.java:165)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:659)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:547)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:111)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:427)
at net.minecraft.server.MinecraftServer$2.run(MinecraftServer.java:685)

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