2014-10-25 14:22:59 [Server thread/ERROR]: Error occurred while enabling ZArena v0.1 (Is it up to date?)
java.lang.NoClassDefFoundError: net/minecraft/server/v1_7_R1/EntityTypes
        at com.github.customentitylibrary.CustomEntityLibrary.getEntityTypesHashMaps(CustomEntityLibrary.java:83) ~[?:?]
        at com.github.customentitylibrary.CustomEntityLibrary.loadCustomEntities(CustomEntityLibrary.java:62) ~[?:?]
        at com.github.customentitylibrary.CustomEntityLibrary.enable(CustomEntityLibrary.java:28) ~[?:?]
        at com.github.zarena.ZArena.onEnable(ZArena.java:73) ~[?:?]
        at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:316) ~[spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:332) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:412) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.loadPlugin(CraftServer.java:476) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at org.bukkit.craftbukkit.v1_7_R4.CraftServer.enablePlugins(CraftServer.java:394) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at net.minecraft.server.v1_7_R4.MinecraftServer.n(MinecraftServer.java:360) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at net.minecraft.server.v1_7_R4.MinecraftServer.g(MinecraftServer.java:334) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at net.minecraft.server.v1_7_R4.MinecraftServer.a(MinecraftServer.java:290) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at net.minecraft.server.v1_7_R4.DedicatedServer.init(DedicatedServer.java:210) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at net.minecraft.server.v1_7_R4.MinecraftServer.run(MinecraftServer.java:458) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at net.minecraft.server.v1_7_R4.ThreadServerApplication.run(SourceFile:628) [spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_7_R1.EntityTypes
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:91) ~[spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot-20141001a.jar:git-Spigot-1.7.9-R0.2-207-g03373bb]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_72]
        at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_72]
        ... 15 more