well then you have two posibilities.
#1 game system is not coded (IE: no monster/npc database being used by the server to spawn things)
#2: your map system is wrong/your player is not being moved around the map via walk/jump/teleport packets in order to trigger the spawning of things
#3: you haven't upgraded the spawn entity/spawnpc/spawnsob packets in order to cause them to be spawned.
If it's a case of not having the packet structures then simply use a proxy or w/e to log the packets and structure them yourself.
There's my proxy thread and also the thread I wrote on packets/proxies/bots which could provide some use.