Bukkit

http://dev.bukkit.org/bukkit-plugins/holographic-displays/

If you run any hd command such as /hd list remap gives this error and crashes all mc clients.

[18:07:59] [Server thread/INFO]: Melonking issued server command: /hd list
[18:07:59] [Server thread/ERROR]: [ReMap] Unhandled exception occured in onPacketSending(PacketEvent) for ReMap
java.lang.ClassCastException: java.lang.String cannot be cast to org.json.simple.JSONObject
    at com.kiwhen.remap.ChatListener$1.onPacketSending(ChatListener.java:43) ~[ReMap.jar:?]
    at com.comphenix.protocol.injector.SortedPacketListenerList.invokeSendingListener(SortedPacketListenerList.java:195) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.SortedPacketListenerList.invokePacketSending(SortedPacketListenerList.java:149) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.PacketFilterManager.handlePacket(PacketFilterManager.java:597) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.PacketFilterManager.invokePacketSending(PacketFilterManager.java:573) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.netty.NettyProtocolInjector.packetQueued(NettyProtocolInjector.java:286) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.netty.NettyProtocolInjector.onPacketSending(NettyProtocolInjector.java:237) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.netty.ChannelInjector.processSending(ChannelInjector.java:199) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.netty.ChannelInjector.access$000(ChannelInjector.java:52) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.netty.ChannelInjector$2.onMessageScheduled(ChannelInjector.java:178) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.netty.ChannelProxy$2.schedulingRunnable(ChannelProxy.java:91) [ProtocolLib.jar:?]
    at com.comphenix.protocol.injector.netty.EventLoopProxy.execute(EventLoopProxy.java:76) [ProtocolLib.jar:?]
    at net.minecraft.server.v1_7_R1.NetworkManager.b(NetworkManager.java:111) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.NetworkManager.handle(NetworkManager.java:89) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.PlayerConnection.sendPacket(PlayerConnection.java:740) [spigot-1322.jar:git-Spigot-1322]
    at org.bukkit.craftbukkit.v1_7_R1.entity.CraftPlayer.sendRawMessage(CraftPlayer.java:140) [spigot-1322.jar:git-Spigot-1322]
    at org.bukkit.craftbukkit.v1_7_R1.entity.CraftPlayer.sendMessage(CraftPlayer.java:147) [spigot-1322.jar:git-Spigot-1322]
    at com.gmail.filoghost.holograms.object.HologramManager.handleSelectedHologramGetList(HologramManager.java:283) [HolographicDisplays.jar:?]
    at com.gmail.filoghost.holograms.CommandHandler.onCommand(CommandHandler.java:98) [HolographicDisplays.jar:?]
    at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) [spigot-1322.jar:git-Spigot-1322]
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:175) [spigot-1322.jar:git-Spigot-1322]
    at org.bukkit.craftbukkit.v1_7_R1.CraftServer.dispatchCommand(CraftServer.java:704) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.PlayerConnection.handleCommand(PlayerConnection.java:972) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java:817) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.PacketPlayInChat.a(PacketPlayInChat.java:28) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.PacketPlayInChat.handle(PacketPlayInChat.java:65) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:147) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.ServerConnection.c(ServerConnection.java:77) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:700) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:273) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:562) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:469) [spigot-1322.jar:git-Spigot-1322]
    at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [spigot-1322.jar:git-Spigot-1322]
[18:07:59] [Server thread/ERROR]: Parameters:
  { a = (("TextComponent{text='', siblings=[], style=Style{hasParent=false, color=null, bold=null, italic=null, underlined=null, obfuscated=null, clickEvent=null, hoverEvent=null}}")), b = true, timestamp = 1393718879916 }