ProtocolLIb Error

[21:01:43] [Server thread/ERROR]:   [ProtocolLib] INTERNAL ERROR: Cannot load ProtocolLib.
  If this problem hasn't already been reported, please open a ticket
  at http://dev.bukkit.org/server-mods/protocollib/ with the following data:
            ===== STACK TRACE =====
  java.lang.IllegalArgumentException: Unable to find a field packetsField with the type java.util.Map in net.minecraft.server.v1_7_R1.Packet; Spigot workaround failed.
  	at com.comphenix.protocol.injector.packet.PacketRegistry.getPacketToID(PacketRegistry.java:99)
  	at com.comphenix.protocol.injector.packet.PacketRegistry.getPacketClassFromID(PacketRegistry.java:284)
  	at com.comphenix.protocol.injector.PacketConstructor.withPacket(PacketConstructor.java:133)
  	at com.comphenix.protocol.injector.server.TemporaryPlayerFactory.<init>(TemporaryPlayerFactory.java:47)
  	at com.comphenix.protocol.injector.player.NetLoginInjector.<init>(NetLoginInjector.java:49)
  	at com.comphenix.protocol.injector.player.ProxyPlayerInjectionHandler.<init>(ProxyPlayerInjectionHandler.java:146)
  	at com.comphenix.protocol.injector.player.PlayerInjectorBuilder.buildHandler(PlayerInjectorBuilder.java:153)
  	at com.comphenix.protocol.injector.PacketFilterManager.<init>(PacketFilterManager.java:245)
  	at com.comphenix.protocol.injector.PacketFilterBuilder.buildInternal(PacketFilterBuilder.java:249)
  	at com.comphenix.protocol.injector.PacketFilterBuilder.build(PacketFilterBuilder.java:232)
  	at com.comphenix.protocol.ProtocolLibrary.onLoad(ProtocolLibrary.java:186)
  	at org.bukkit.craftbukkit.v1_7_R1.CraftServer.loadPlugins(CraftServer.java:260)
  	at org.bukkit.craftbukkit.v1_7_R1.CraftServer.reload(CraftServer.java:628)
  	at org.bukkit.Bukkit.reload(Bukkit.java:279)
  	at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:23)
  	at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:192)
  	at org.bukkit.craftbukkit.v1_7_R1.CraftServer.dispatchCommand(CraftServer.java:542)
  	at net.minecraft.server.v1_7_R1.PlayerConnection.handleCommand(PlayerConnection.java:930)
  	at net.minecraft.server.v1_7_R1.PlayerConnection.a(PlayerConnection.java:812)
  	at net.minecraft.server.v1_7_R1.PacketPlayInChat.a(PacketPlayInChat.java:28)
  	at net.minecraft.server.v1_7_R1.PacketPlayInChat.handle(PacketPlayInChat.java:47)
  	at net.minecraft.server.v1_7_R1.NetworkManager.a(NetworkManager.java:146)
  	at net.minecraft.server.v1_7_R1.ServerConnection.c(SourceFile:134)
  	at net.minecraft.server.v1_7_R1.MinecraftServer.u(MinecraftServer.java:651)
  	at net.minecraft.server.v1_7_R1.DedicatedServer.u(DedicatedServer.java:250)
  	at net.minecraft.server.v1_7_R1.MinecraftServer.t(MinecraftServer.java:541)
  	at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:453)
  	at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617)
  Caused by: java.lang.IllegalArgumentException: Unable to find a field that matches {modifiers=[required: 0, banned: 0], type={
    methods=[{modifiers=[required: 0, banned: 0], name=\Qsize\E, return=Exact int}, {modifiers=[required: 0, banned: 0], name=\Qput\E, paramCount=2}, {modifiers=[required: 0, banned: 0], name=\Qget\E, paramCount=1}]
  }}
  	at com.comphenix.protocol.reflect.FuzzyReflection.getField(FuzzyReflection.java:326)
  	at com.comphenix.protocol.injector.packet.PacketRegistry.getSpigotWrapper(PacketRegistry.java:137)
  	at com.comphenix.protocol.injector.packet.PacketRegistry.getPacketToID(PacketRegistry.java:96)
  	... 27 more
            ===== DUMP =====
  Parameters:
    [NULL]
  Sender:
    com.comphenix.protocol.ProtocolLibrary@175b5516[
      statistisc=<null>
      backgroundCompiler=<null>
      asyncPacketTask=-1
      tickCounter=0
      unhookTask=com.comphenix.protocol.injector.DelayedSingleTask@4a54b23c
      config=com.comphenix.protocol.ProtocolConfig@7e81a743
      updater=com.comphenix.protocol.metrics.Updater@720c6097
      updateDisabled=false
      logger=org.bukkit.plugin.PluginLogger@a999400
      redirectHandler=<null>
      commandProtocol=<null>
      commandPacket=<null>
      commandFilter=<null>
      skipDisable=false
      isEnabled=false
      initialized=true
      loader=org.bukkit.plugin.java.JavaPluginLoader@68c3916f
      server=CraftServer{serverName=CraftBukkit,serverVersion=git-Bukkit-1.6.4-R2.0-28-g373cbb7-b2945jnks,minecraftVersion=1.7.2}
      file=plugins/ProtocolLib-2.7.3.jar
      description=org.bukkit.plugin.PluginDescriptionFile@7f814424
      dataFolder=plugins/ProtocolLib
      classLoader=org.bukkit.plugin.java.PluginClassLoader@2deba40c
      naggable=true
      ebean=<null>
      newConfig=YamlConfiguration[path='', root='YamlConfiguration']
      configFile=plugins/ProtocolLib/config.yml
      logger=org.bukkit.plugin.PluginLogger@a999400
    ]
  Version:
    ProtocolLib v2.7.3
  Server:
    git-Bukkit-1.6.4-R2.0-28-g373cbb7-b2945jnks (MC: 1.7.2)