*Update to Mangos 6856. Source: Mangos.

--HG--
branch : trunk

src/game/PetHandler.cpp

@@ -112,7 +112,10 @@ void WorldSession::HandlePetAction( WorldPacket & recv_data )
                         return;
 
                     // not let attack friendly units.
-                    if( GetPlayer()->IsFriendlyTo(TargetUnit))
+                    if(GetPlayer()->IsFriendlyTo(TargetUnit))
+                        return;
+                    // Not let attack through obstructions
+                    if(!pet->IsWithinLOSInMap(TargetUnit))
                         return;
 
                     if(pet->GetTypeId() != TYPEID_PLAYER)