Minestrike error

Could not load 'plugins\MS.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.jar:git-Spigot-06ad352-4a7472d]
        at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:329) ~[spigot.jar:git-Spigot-06ad352-4a7472d]
        at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) [spigot.jar:git-Spigot-06ad352-4a7472d]
        at org.bukkit.craftbukkit.v1_8_R3.CraftServer.loadPlugins(CraftServer.java:292) [spigot.jar:git-Spigot-06ad352-4a7472d]
        at net.minecraft.server.v1_8_R3.DedicatedServer.init(DedicatedServer.java:198) [spigot.jar:git-Spigot-06ad352-4a7472d]
        at net.minecraft.server.v1_8_R3.MinecraftServer.run(MinecraftServer.java:525) [spigot.jar:git-Spigot-06ad352-4a7472d]
        at java.lang.Thread.run(Unknown Source) [?:1.8.0_60]
Caused by: java.lang.NoClassDefFoundError: net/minecraft/server/v1_8_R2/Packet
        at A3.MS.MS.<init>(MS.java:83) ~[?:?]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_60]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_60]
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_60]
        at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[?:1.8.0_60]
        at java.lang.Class.newInstance(Unknown Source) ~[?:1.8.0_60]
        at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:76) ~[spigot.jar:git-Spigot-06ad352-4a7472d]
        at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[spigot.jar:git-Spigot-06ad352-4a7472d]
        ... 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.jar:git-Spigot-06ad352-4a7472d]
        at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot.jar:git-Spigot-06ad352-4a7472d]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_60]
        at java.lang.ClassLoader.loadClass(Unknown Source) ~[?:1.8.0_60]
        at A3.MS.MS.<init>(MS.java:83) ~[?:?]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method) ~[?:1.8.0_60]
        at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_60]
        at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source) ~[?:1.8.0_60]
        at java.lang.reflect.Constructor.newInstance(Unknown Source) ~[?:1.8.0_60]
        at java.lang.Class.newInstance(Unknown Source) ~[?:1.8.0_60]
        at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:76) ~[spigot.jar:git-Spigot-06ad352-4a7472d]
        at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[spigot.jar:git-Spigot-06ad352-4a7472d]
        ... 6 more