Again Error

00:10:13 [SEVERE] null loading SimplePl v1.0 (Is it up to date?)
java.lang.NullPointerException
        at org.bukkit.command.PluginCommandYamlParser.parse(PluginCommandYamlPar
ser.java:26)
        at org.bukkit.plugin.SimplePluginManager.enablePlugin(SimplePluginManage
r.java:373)
        at org.bukkit.craftbukkit.CraftServer.loadPlugin(CraftServer.java:199)
        at org.bukkit.craftbukkit.CraftServer.enablePlugins(CraftServer.java:182
)
        at net.minecraft.server.MinecraftServer.t(MinecraftServer.java:357)
        at net.minecraft.server.MinecraftServer.a(MinecraftServer.java:344)
        at net.minecraft.server.MinecraftServer.init(MinecraftServer.java:175)
        at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:408)
        at net.minecraft.server.ThreadServerApplication.run(SourceFile:465)