Implemented OfflinePlayer

src/main/java/org/bukkit/craftbukkit/CraftServer.java

@@ -806,4 +806,14 @@ public final class CraftServer implements Server {
 
         return count;
     }
+
+    public OfflinePlayer getOfflinePlayer(String name) {
+        OfflinePlayer result = getPlayer(name);
+
+        if (result == null) {
+            result = new CraftOfflinePlayer(this, name);
+        }
+
+        return result;
+    }
 }

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

@@ -16,7 +16,7 @@ import org.bukkit.plugin.Plugin;
 
 public class CraftHumanEntity extends CraftLivingEntity implements HumanEntity {
     private CraftInventoryPlayer inventory;
-    private final PermissibleBase perm = new PermissibleBase(this);
+    protected final PermissibleBase perm = new PermissibleBase(this);
     private boolean op;
 
     public CraftHumanEntity(final CraftServer server, final EntityHuman entity) {
@@ -110,7 +110,8 @@ public class CraftHumanEntity extends CraftLivingEntity implements HumanEntity {
 
     public void setOp(boolean value) {
         this.op = value;
-        recalculatePermissions();
+        perm.recalculatePermissions();
+        perm.calculatePermissions();
     }
 
     public Set<PermissionAttachmentInfo> getEffectivePermissions() {

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

@@ -47,6 +47,9 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
         } else {
             server.getHandle().f(getName());
         }
+
+        perm.recalculatePermissions();
+        perm.calculatePermissions();
     }
 
     public boolean isPlayer() {