Adds update chunk method for sending fake chunk updates to the client. This is to match the sendBlockChange method.

src/main/java/net/minecraft/server/Packet51MapChunk.java

@@ -0,0 +1,95 @@
+package net.minecraft.server;
+
+import java.io.DataInputStream;
+import java.io.DataOutputStream;
+import java.io.IOException;
+import java.util.zip.DataFormatException;
+import java.util.zip.Deflater;
+import java.util.zip.Inflater;
+
+public class Packet51MapChunk extends Packet {
+
+    public int a;
+    public int b;
+    public int c;
+    public int d;
+    public int e;
+    public int f;
+    public byte[] g;
+    private int h;
+
+    public Packet51MapChunk() {
+        this.k = true;
+    }
+
+    // CraftBukkit - start
+    public Packet51MapChunk(int i, int j, int k, int l, int i1, int j1, World world) {
+        this(i, j, k, l, i1, j1, world.c(i, j, k, l, i1, j1));
+    }
+
+    public Packet51MapChunk(int i, int j, int k, int l, int i1, int j1, byte[] data) {
+    // CraftBukkit - end
+        this.k = true;
+        this.a = i;
+        this.b = j;
+        this.c = k;
+        this.d = l;
+        this.e = i1;
+        this.f = j1;
+        byte[] abyte = data; // CraftBukkit - uses data from above constructor
+        Deflater deflater = new Deflater(1);
+
+        try {
+            deflater.setInput(abyte);
+            deflater.finish();
+            this.g = new byte[l * i1 * j1 * 5 / 2];
+            this.h = deflater.deflate(this.g);
+        } finally {
+            deflater.end();
+        }
+    }
+
+    public void a(DataInputStream datainputstream) throws IOException { // CraftBukkit - throws IOEXception
+        this.a = datainputstream.readInt();
+        this.b = datainputstream.readShort();
+        this.c = datainputstream.readInt();
+        this.d = datainputstream.read() + 1;
+        this.e = datainputstream.read() + 1;
+        this.f = datainputstream.read() + 1;
+        this.h = datainputstream.readInt();
+        byte[] abyte = new byte[this.h];
+
+        datainputstream.readFully(abyte);
+        this.g = new byte[this.d * this.e * this.f * 5 / 2];
+        Inflater inflater = new Inflater();
+
+        inflater.setInput(abyte);
+
+        try {
+            inflater.inflate(this.g);
+        } catch (DataFormatException dataformatexception) {
+            throw new IOException("Bad compressed data format");
+        } finally {
+            inflater.end();
+        }
+    }
+
+    public void a(DataOutputStream dataoutputstream) throws IOException { // CraftBukkit - throws IOException
+        dataoutputstream.writeInt(this.a);
+        dataoutputstream.writeShort(this.b);
+        dataoutputstream.writeInt(this.c);
+        dataoutputstream.write(this.d - 1);
+        dataoutputstream.write(this.e - 1);
+        dataoutputstream.write(this.f - 1);
+        dataoutputstream.writeInt(this.h);
+        dataoutputstream.write(this.g, 0, this.h);
+    }
+
+    public void a(NetHandler nethandler) {
+        nethandler.a(this);
+    }
+
+    public int a() {
+        return 17 + this.h;
+    }
+}

src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java

@@ -2,11 +2,13 @@ package org.bukkit.craftbukkit.entity;
 
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
+import java.util.zip.Deflater;
 import net.minecraft.server.EntityHuman;
 import net.minecraft.server.EntityPlayer;
 import net.minecraft.server.ItemInWorldManager;
 import net.minecraft.server.Packet200Statistic;
 import net.minecraft.server.Packet3Chat;
+import net.minecraft.server.Packet51MapChunk;
 import net.minecraft.server.Packet53BlockChange;
 import net.minecraft.server.Packet54PlayNoteBlock;
 import net.minecraft.server.Packet6SpawnPosition;
@@ -164,6 +166,33 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         getHandle().netServerHandler.sendPacket(packet);
     }
 
+    public boolean sendChunkChange(Location loc, int sx, int sy, int sz, byte[] data) {
+        int x = loc.getBlockX();
+        int y = loc.getBlockY();
+        int z = loc.getBlockZ();
+
+        int cx = x >> 4;
+        int cz = z >> 4;
+
+        if (sx <= 0 || sy <= 0 || sz <= 0) {
+            return false;
+        }
+
+        if ((x + sx - 1) >> 4 != cx || (z + sz - 1) >> 4 != cz || y < 0 || y + sy > 128) {
+            return false;
+        }
+
+        if (data.length != (sx * sy * sz * 5) / 2) {
+            return false;
+        }
+
+        Packet51MapChunk packet = new Packet51MapChunk(x, y, z, sx, sy, sz, data);
+
+        getHandle().netServerHandler.sendPacket(packet);
+
+        return true;
+    }
+
     @Override
     public boolean teleport(Location location) {
         WorldServer oldWorld = ((CraftWorld)getWorld()).getHandle();