Bukkit

Bekomme folgenden Fehler mit Spigot 1.8

[17:52:09] [Server thread/ERROR]: Could not load 'plugins/miniconomy.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: com/spongybacon/minieconomy/MiniEconomy : Unsupported major.minor version 52.0
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:135) ~[spigot_server.jar:git-Spigot-870264a-0a645a2]
    at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:329) ~[spigot_server.jar:git-Spigot-870264a-0a645a2]
    at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:251) [spigot_server.jar:git-Spigot-870264a-0a645a2]
    at org.bukkit.craftbukkit.v1_8_R2.CraftServer.loadPlugins(CraftServer.java:291) [spigot_server.jar:git-Spigot-870264a-0a645a2]
    at net.minecraft.server.v1_8_R2.DedicatedServer.init(DedicatedServer.java:199) [spigot_server.jar:git-Spigot-870264a-0a645a2]
    at net.minecraft.server.v1_8_R2.MinecraftServer.run(MinecraftServer.java:522) [spigot_server.jar:git-Spigot-870264a-0a645a2]
    at java.lang.Thread.run(Thread.java:745) [?:1.7.0_75]
Caused by: java.lang.UnsupportedClassVersionError: com/spongybacon/minieconomy/MiniEconomy : Unsupported major.minor version 52.0
    at java.lang.ClassLoader.defineClass1(Native Method) ~[?:1.7.0_75]
    at java.lang.ClassLoader.defineClass(ClassLoader.java:800) ~[?:1.7.0_75]
    at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142) ~[?:1.7.0_75]
    at java.net.URLClassLoader.defineClass(URLClassLoader.java:449) ~[?:1.7.0_75]
    at java.net.URLClassLoader.access$100(URLClassLoader.java:71) ~[?:1.7.0_75]
    at java.net.URLClassLoader$1.run(URLClassLoader.java:361) ~[?:1.7.0_75]
    at java.net.URLClassLoader$1.run(URLClassLoader.java:355) ~[?:1.7.0_75]
    at java.security.AccessController.doPrivileged(Native Method) ~[?:1.7.0_75]
    at java.net.URLClassLoader.findClass(URLClassLoader.java:354) ~[?:1.7.0_75]
    at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:101) ~[spigot_server.jar:git-Spigot-870264a-0a645a2]
    at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:86) ~[spigot_server.jar:git-Spigot-870264a-0a645a2]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:425) ~[?:1.7.0_75]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:358) ~[?:1.7.0_75]
    at java.lang.Class.forName0(Native Method) ~[?:1.7.0_75]
    at java.lang.Class.forName(Class.java:274) ~[?:1.7.0_75]
    at org.bukkit.plugin.java.PluginClassLoader.<init>(PluginClassLoader.java:64) ~[spigot_server.jar:git-Spigot-870264a-0a645a2]
    at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:131) ~[spigot_server.jar:git-Spigot-870264a-0a645a2]
    ... 6 more