Bukkit

What steps will reproduce the problem?
1. Not sure, it popped up supposedly after an explosion
2.
3.

What is the expected output? What do you see instead?
Install plugin, explode creepers

What version of the product are you using?
Latest

Do you have an error log of what happened?

Yes

06.10 20:50:13 [Server] WARN at java.lang.Thread.run(Thread.java:745)
06.10 20:50:13 [Server] WARN at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:557)
06.10 20:50:13 [Server] WARN at net.minecraft.server.v1_8_R3.MinecraftServer.A(MinecraftServer.java:654)
06.10 20:50:13 [Server] WARN at net.minecraft.server.v1_8_R3.DedicatedServer.B(DedicatedServer.java:374)
06.10 20:50:13 [Server] WARN at net.minecraft.server.v1_8_R3.MinecraftServer.B(MinecraftServer.java:723)
06.10 20:50:13 [Server] WARN at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftScheduler.mainThreadHeartbeat(CraftScheduler.java:350)
06.10 20:50:13 [Server] WARN at org.bukkit.craftbukkit.v1_8_R3.scheduler.CraftTask.run(CraftTask.java:71)
06.10 20:50:13 [Server] WARN at com.nitnelave.CreeperHeal.block.ExplodedBlockManager$2.run(ExplodedBlockManager.java:297)
06.10 20:50:13 [Server] WARN at com.nitnelave.CreeperHeal.block.ExplodedBlockManager.access$1(ExplodedBlockManager.java:216)
06.10 20:50:13 [Server] WARN at com.nitnelave.CreeperHeal.block.ExplodedBlockManager.checkReplace(ExplodedBlockManager.java:222)
06.10 20:50:13 [Server] WARN at com.nitnelave.CreeperHeal.block.CreeperExplosion.checkReplace(CreeperExplosion.java:342)
06.10 20:50:13 [Server] WARN at com.nitnelave.CreeperHeal.block.CreeperExplosion.replace_one_block(CreeperExplosion.java:167)
06.10 20:50:13 [Server] WARN at com.nitnelave.CreeperHeal.block.CreeperBlock.replace(CreeperBlock.java:247)
06.10 20:50:13 [Server] WARN at com.nitnelave.CreeperHeal.block.CreeperChest.update(CreeperChest.java:149)
06.10 20:50:13 [Server] WARN java.lang.ClassCastException: org.bukkit.craftbukkit.v1_8_R3.block.CraftBlockState cannot be cast to org.bukkit.inventory.InventoryHolder
06.10 20:50:13 [Server] WARN AIR at 709; 81; 1077
06.10 20:50:13 [Server] WARN org.bukkit.craftbukkit.v1_8_R3.block.CraftBlock
06.10 20:50:13 [Server] WARN ClassCastException when replacing a chest :
06.10 20:50:13 [Server] WARN Error detected, please report the whole message

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