NOTE TO ALL PEOPLE PLAYING THIS:
You must have MoC *SMP*.
Also, Ill try this server, as my MoC server has ridiculous spawn rate issues. First, the invasion of the polar bears. Then countless server restarts/config edits. Now there are boatloads of creatures in teh first few chunks that are stopping the spawn of others. Hopefully yours is better. See you there!
Edit: Apparently the server is not up. Is this server dedicated? Also, some more info would help. Like which plugins there are? Etc.