CraftWorld change

So, regarding org.bukkit.craftbukkit.v1_5_R1.CraftWorld, since the update there is a new argument for the setData method... Can anyone help me out in trying to figure out what it is/does?

I refactored a bit just to clean things up:

Code:java

 
    public boolean setData(int x, int y, int z, int type, int mysteryVariable)
    {
        if (x >= -30000000 && z >= -30000000 && x < 30000000 && z < 30000000) {
            if (y < 0) {
                return false;
            } else if (y >= 256) {
                return false;
            } else {
                Chunk chunk = this.getChunkAt(x >> 4, z >> 4);
                int j1 = x & 15;
                int k1 = z & 15;
                boolean flag = chunk.b(j1, y, k1, type);
 
                if (flag) {
                    int l1 = chunk.getTypeId(j1, y, k1);
 
                    if ((mysteryVariable & 2) != 0 && (!this.isStatic || (mysteryVariable & 4) == 0)) {
                        this.notify(x, y, z);
                    }
 
                    if (!this.isStatic && (mysteryVariable & 1) != 0) {
                        this.update(x, y, z, l1);
                        Block block = Block.byId[l1];
 
                        if (block != null && block.q_()) {
                            this.m(x, y, z, l1);
                        }
                    }
                }
 
                return flag;
            }
        } else {
            return false;
        }
    }

 

I think its a variable that looks if physics events are thrown, play with it to see