Mob spawners
Hi
Is it possible to change in a multiplayer server the mobs of a player-placed mob spawner?
Kefwar
Yes, although not on Vanilla (original Minecraft)
You will need bukkit, and a plugin.
There should be a plugin for bukkit that can help you with that. But any client mods wont help, because they are for SP
if your OP, you can custom spawn animals