ClearLag 2.6.0 Crash Report

INFO] [ClearLag] Enabling ClearLag v2.6.0
2013-10-15 20:31:21 [SEVERE] Error occurred while enabling ClearLag v2.6.0 (Is it up to date?)
java.lang.NoClassDefFoundError: net/minecraft/server/v1_6_R3/Entity
	at me.minebuilders.clearlag.Clearlag.addListeners(Clearlag.java:114)
	at me.minebuilders.clearlag.Clearlag.onEnable(Clearlag.java:67)
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:217)
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:484)
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:382)
	at org.bukkit.craftbukkit.v1_6_R4.CraftServer.loadPlugin(CraftServer.java:296)
	at org.bukkit.craftbukkit.v1_6_R4.CraftServer.enablePlugins(CraftServer.java:278)
	at net.minecraft.server.MinecraftServer.func_71243_i(MinecraftServer.java:509)
	at net.minecraft.server.MinecraftServer.func_71222_d(MinecraftServer.java:473)
	at net.minecraft.server.MinecraftServer.func_71247_a(MinecraftServer.java:422)
	at net.minecraft.server.dedicated.DedicatedServer.func_71197_b(DedicatedServer.java:222)
	at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:618)
	at net.minecraft.server.ThreadMinecraftServer.run(ThreadMinecraftServer.java:16)
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_6_R3.Entity
	at org.bukkit.plugin.java.PluginClassLoader.findClass0(PluginClassLoader.java:451)
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:245)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	... 13 more