private static final WorldType HEURISTIC_WORLDTYPE = new WorldType("no-op") {
        @Override public IChunkGenerator getChunkGenerator(World world, String options) {
            return null; // now thats something we can detect >:D
        }
    };

//in constructor:

        boolean useProvider = false;

        if (!world.isRemote) {
            if (world.getWorldType() instanceof ICubicWorldType) { // Who do we trust!??!?! D:

                // nasty hack heuristic to see if provider asks its WorldType for a chunk generator
                //ReflectionUtil.setFieldValueSrg(wp, "field_76577_b", HEURISTIC_WORLDTYPE);
                provider.terrainType = HEURISTIC_WORLDTYPE;

                IChunkGenerator pro_or_null = provider.createChunkGenerator();

                // clean up
                //ReflectionUtil.setFieldValueSrg(provider, "field_76577_b", worldObj.getWorldType());
                provider.terrainType = world.getWorldType();

                if (pro_or_null != null) { // It will be null if it tries to get one form WorldType

                    // It was from a vanilla WorldProvider... use it
                    cubeGen = new VanillaCompatibilityGenerator(pro_or_null, worldIn);
                } else {

                    // It was from WorldType, try to use cubic generator
                    cubeGen = ((ICubicWorldType) world.getWorldType()).createCubeGenerator(getCubicWorld());
                    if (cubeGen == null) {
                        useProvider = true;
                    }
                }
            } else {
                useProvider = true;
            }

            if (useProvider) {
                cubeGen = new VanillaCompatibilityGenerator(provider.createChunkGenerator(), worldIn);
            }
        }