MultiVerse

16:26:38 [SEVERE] Error occurred while enabling Multiverse-Core v2.5-b641 (Is it up to date?)
java.lang.NoClassDefFoundError: net/minecraft/server/v1_5_R2/World
	at uk.co.jacekk.bukkit.skylandsplus.SkylandsPlus.getDefaultWorldGenerator(SkylandsPlus.java:32)
	at org.bukkit.WorldCreator.getGeneratorForName(WorldCreator.java:284)
	at org.bukkit.WorldCreator.generator(WorldCreator.java:181)
	at com.onarandombox.MultiverseCore.utils.WorldManager.doLoad(WorldManager.java:374)
	at com.onarandombox.MultiverseCore.utils.WorldManager.doLoad(WorldManager.java:359)
	at com.onarandombox.MultiverseCore.utils.WorldManager.loadWorlds(WorldManager.java:650)
	at com.onarandombox.MultiverseCore.MultiverseCore.onEnable(MultiverseCore.java:304)
	at org.bukkit.plugin.java.JavaPlugin.setEnabled(JavaPlugin.java:217)
	at org.bukkit.plugin.java.JavaPluginLoader.enablePlugin(JavaPluginLoader.java:457)
	at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManager.java:381)
	at org.bukkit.craftbukkit.v1_5_R3.CraftServer.loadPlugin(CraftServer.java:282)
	at org.bukkit.craftbukkit.v1_5_R3.CraftServer.enablePlugins(CraftServer.java:264)
	at net.minecraft.server.v1_5_R3.MinecraftServer.j(MinecraftServer.java:304)
	at net.minecraft.server.v1_5_R3.MinecraftServer.e(MinecraftServer.java:283)
	at net.minecraft.server.v1_5_R3.MinecraftServer.a(MinecraftServer.java:243)
	at net.minecraft.server.v1_5_R3.DedicatedServer.init(DedicatedServer.java:151)
	at net.minecraft.server.v1_5_R3.MinecraftServer.run(MinecraftServer.java:382)
	at net.minecraft.server.v1_5_R3.ThreadServerApplication.run(SourceFile:573)
Caused by: java.lang.ClassNotFoundException: net.minecraft.server.v1_5_R2.World
	at org.bukkit.plugin.java.PluginClassLoader.findClass0(PluginClassLoader.java:70)
	at org.bukkit.plugin.java.PluginClassLoader.findClass(PluginClassLoader.java:53)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:423)
	at java.lang.ClassLoader.loadClass(ClassLoader.java:356)
	... 18 more