Bukkit

What steps will reproduce the problem?
1. Could not load 'plugins/Quake (2).jar' in folder 'plugins'

What is the expected output? What do you see instead? Error Log:

[18:20:44] [Server thread/ERROR]: Could not load 'plugins/Quake (2).jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.NoClassDefFoundError: net/minecraft/server/v1_7_R1/Packet
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[server.jar:git-Spigot-1356]
    at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:329) ~[server.jar:git-Spigot-1356]
    at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) [server.jar:git-Spigot-1356]
    at org.bukkit.craftbukkit.v1_7_R2.CraftServer.loadPlugins(CraftServer.java:356) [server.jar:git-Spigot-1356]
    at org.bukkit.craftbukkit.v1_7_R2.CraftServer.reload(CraftServer.java:797) [server.jar:git-Spigot-1356]
    at org.bukkit.Bukkit.reload(Bukkit.java:279) [server.jar:git-Spigot-1356]
    at org.bukkit.command.defaults.ReloadCommand.execute(ReloadCommand.java:24) [server.jar:git-Spigot-1356]
    at org.bukkit.command.SimpleCommandMap.dispatch(SimpleCommandMap.java:180) [server.jar:git-Spigot-1356]
    at org.bukkit.craftbukkit.v1_7_R2.CraftServer.dispatchCommand(CraftServer.java:709) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.PlayerConnection.handleCommand(PlayerConnection.java:984) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.PlayerConnection.a(PlayerConnection.java:829) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.PacketPlayInChat.a(PacketPlayInChat.java:28) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.PacketPlayInChat.handle(PacketPlayInChat.java:65) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.NetworkManager.a(NetworkManager.java:148) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.ServerConnection.c(ServerConnection.java:77) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.MinecraftServer.v(MinecraftServer.java:703) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.DedicatedServer.v(DedicatedServer.java:273) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.MinecraftServer.u(MinecraftServer.java:566) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.MinecraftServer.run(MinecraftServer.java:472) [server.jar:git-Spigot-1356]
    at net.minecraft.server.v1_7_R2.ThreadServerApplication.run(SourceFile:618) [server.jar:git-Spigot-1356]
Caused by: java.lang.NoClassDefFoundError: net/minecraft/server/v1_7_R1/Packet
    at java.lang.Class.forName0(Native Method) ~[?:1.7.0_25]
    at java.lang.Class.forName(Class.java:270) ~[?:1.7.0_25]
    at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:40) ~[server.jar:git-Spigot-1356]
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:127) ~[server.jar:git-Spigot-1356]
    ... 19 more
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_7_R1.Packet
    at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:67) ~[server.jar:git-Spigot-1356]
    at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:62) ~[server.jar:git-Spigot-1356]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[?:1.7.0_25]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[?:1.7.0_25]
    at java.lang.Class.forName0(Native Method) ~[?:1.7.0_25]
    at java.lang.Class.forName(Class.java:270) ~[?:1.7.0_25]
    at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:40) ~[server.jar:git-Spigot-1356]
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:127) ~[server.jar:git-Spigot-1356]
    ... 19 more

What version of the product are you using?

The Newest

Please provide any additional information below.

Please Update to 1.7.5