Bukkit

What steps will reproduce the problem?
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What is the expected output? What do you see instead?

What version of the product are you using? Just downloaded the latest 3.3 & 3.4

Do you have an error log of what happened?
12:05:53 [SEVERE] Could not load 'plugins\WorldWarp.jar' in folder 'plugins'
org.bukkit.plugin.InvalidPluginException: java.lang.UnsupportedClassVersionError: Raz/WorldWarp/WorldWarp : Unsupported major.minor version 51.0
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:184)
at org.bukkit.plugin.SimplePluginManager.loadPlugin(SimplePluginManager.java:305)
at org.bukkit.plugin.SimplePluginManager.loadPlugins(SimplePluginManager.java:230)
at org.bukkit.craftbukkit.v1_5_R2.CraftServer.loadPlugins(CraftServer.java:239)
at org.bukkit.craftbukkit.v1_5_R2.CraftServer.<init>(CraftServer.java:217)
at net.minecraft.server.v1_5_R2.PlayerList.<init>(PlayerList.java:55)
at net.minecraft.server.v1_5_R2.DedicatedPlayerList.<init>(SourceFile:11)
at net.minecraft.server.v1_5_R2.DedicatedServer.init(DedicatedServer.java:105)
at net.minecraft.server.v1_5_R2.MinecraftServer.run(MinecraftServer.java:381)
at net.minecraft.server.v1_5_R2.ThreadServerApplication.run(SourceFile:573)
Caused by: java.lang.UnsupportedClassVersionError: Raz/WorldWarp/WorldWarp : Unsupported major.minor version 51.0
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClassCond(Unknown Source)
at java.lang.ClassLoader.defineClass(Unknown Source)
at java.security.SecureClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.defineClass(Unknown Source)
at java.net.URLClassLoader.access$000(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at org.bukkit.plugin.java.PluginClassLoader.findClass0(PluginClassLoader.java:80)
at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:53)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at org.bukkit.plugin.java.JavaPluginLoader.loadPlugin(JavaPluginLoader.java:173)
... 9 more

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