Bukkit

What steps will reproduce the problem?
1. Maybe, I have installed vault and worldedit

What is the expected output? What do you see instead?

The plugin is not starting or working.

What version of the product are you using?

B: Quake - Beta V2.4.0 for 1.7.2 Dec 15, 2013

Do you have an error log of what happened?

[08:59:56 ERROR]: Could not load 'plugins/Quake.jar' in folder 'plugins' org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: com/Geekpower14/Quake/Quake : Unsupported major.minor version 51.0 at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:137) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:308) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:231) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at org.bukkit.craftbukkit.v1_7_R1.CraftServer.loadPlugins(CraftServer.java:257) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at org.bukkit.craftbukkit.v1_7_R1.CraftServer.<init>(CraftServer.java:235) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at net.minecraft.server.v1_7_R1.PlayerList.<init>(PlayerList.java:63) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at net.minecraft.server.v1_7_R1.DedicatedPlayerList.<init>(SourceFile:14) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at net.minecraft.server.v1_7_R1.DedicatedServer.init(DedicatedServer.java:126) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at net.minecraft.server.v1_7_R1.MinecraftServer.run(MinecraftServer.java:424) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at net.minecraft.server.v1_7_R1.ThreadServerApplication.run(SourceFile:617) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] Caused by: java.lang.UnsupportedClassVersionError: com/Geekpower14/Quake/Quake : Unsupported major.minor version 51.0 at java.lang.ClassLoader.defineClass1(Native Method) [?:1.6.0_65] at java.lang.ClassLoader.defineClassCond(ClassLoader.java:637) [?:1.6.0_65] at java.lang.ClassLoader.defineClass(ClassLoader.java:621) [?:1.6.0_65] at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141) [?:1.6.0_65] at java.net.URLClassLoader.defineClass(URLClassLoader.java:283) [?:1.6.0_65] at java.net.URLClassLoader.access$000(URLClassLoader.java:58) [?:1.6.0_65] at java.net.URLClassLoader$1.run(URLClassLoader.java:197) [?:1.6.0_65] at java.security.AccessController.doPrivileged(Native Method) [?:1.6.0_65] at java.net.URLClassLoader.findClass(URLClassLoader.java:190) [?:1.6.0_65] at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:77) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:62) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at java.lang.ClassLoader.loadClass(ClassLoader.java:306) [?:1.6.0_65] at java.lang.ClassLoader.loadClass(ClassLoader.java:247) [?:1.6.0_65] at java.lang.Class.forName0(Native Method) [?:1.6.0_65] at java.lang.Class.forName(Class.java:249) [?:1.6.0_65] at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:40) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:133) [craftbukkit.jar:git-Bukkit-1.7.2-R0.2-15-g2f3dbd3-b2992jnks] ... 9 more

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