Bukkit

Summary:
The plugin can't load at all. I get a "NoClassDefFoundError" error

DisguiseCraft version:
v5.1

ProtocolLib V3.6.4

CraftBukkit version:
CB-1.#.#-R#.#
Spigot 1.8.8

Console Log (if any):
<<code>>
Set PluginClassLoader as parallel capable
[09:03:50 ERROR]: Could not load 'plugins/DisguiseCraft5.1.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.NoClassDefFoundError: net/minecraft/server/v1_8_R2/Packet
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:135) ~[spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:329) ~[spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) [spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugins(CraftServer.java:292) [spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:198) [spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:525) [spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at java.lang.Thread.run(Thread.java:745) [?:1.7.0_91]
Caused by: java.lang.NoClassDefFoundError: net/minecraft/server/v1_8_R2/Packet
    at java.lang.Class.forName0(Native Method) ~[?:1.7.0_91]
    at java.lang.Class.forName(Class.java:278) ~[?:1.7.0_91]
    at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:64) ~[spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    ... 6 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_8_R2.Packet
    at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:91) ~[spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_91]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_91]
    at java.lang.Class.forName0(Native Method) ~[?:1.7.0_91]
    at java.lang.Class.forName(Class.java:278) ~[?:1.7.0_91]
    at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:64) ~[spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[spigot-1.8.8.jar:git-Spigot-db6de12-d3e0b6f]
    ... 6 more

<</code>>

Steps to reproduce:
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List of plugins also on the server:

Additional information: