Rejected Weird error with toString() in EntityType enum.

No idea what is causing this, but when I try using .toString() with a EntityType enum that has a underscore in its name I get a NullPointerException.

The error:

Code (Text):

19:16:39 [SEVERE] Error occurred while enabling MobArena v1.0 (Is it up to date?)
java.lang.NullPointerException
at com.funkiserver.mobarena.Game.setAllowedMobs(Game.java:169)
at com.funkiserver.mobarena.MobArena.reloadGamesFromConfig(MobArena.java:209)
at com.funkiserver.mobarena.MobArena.onEnable(MobArena.java:62)
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:382)
at org.bukkit.craftbukkit.v1_6_R2.CraftServer.loadPlugin(CraftServer.java:286)
at org.bukkit.craftbukkit.v1_6_R2.CraftServer.enablePlugins(CraftServer.java:268)
at net.minecraft.server.v1_6_R2.MinecraftServer.l(MinecraftServer.java:319)
at net.minecraft.server.v1_6_R2.MinecraftServer.f(MinecraftServer.java:296)
at net.minecraft.server.v1_6_R2.MinecraftServer.a(MinecraftServer.java:256)
at net.minecraft.server.v1_6_R2.DedicatedServer.init(DedicatedServer.java:164)
at net.minecraft.server.v1_6_R2.MinecraftServer.run(MinecraftServer.java:397)
at net.minecraft.server.v1_6_R2.ThreadServerApplication.run(SourceFile:582)
 

My code:

Code (Text):

public void setAllowedMobs(List<EntityType> mobs) {
    allowedMobs = mobs;
    List<String> names = new ArrayList<String>();
    for (EntityType mob : allowedMobs) {
        names.add(mob.toString()); //line 169
    }
    plugin.getConfig().set("arenas." + name + ".allowed_mobs",names);
}

 

I'm using EntityType.fromName() to convert strings from the config to EntityType's, and I think this is whats causing the null elements. It was was working with everything until I tried CAVE_SPIDER and PIG_ZOMBIE. I made this instead and it works:

Code (Text):

public EntityType getEntityTypeFromName(String name) {
    for (EntityType entityType : EntityType.values()) {
        if (entityType.toString().equals(name)) {
            return entityType;
        }
    }
    return null;
}