http://bukkit.fr/index.php?threads/9258/

PickYoSpawner.java

package fr.neatmonster.pickyospawner;

import org.bukkit.Location;
import org.bukkit.Material;
import org.bukkit.event.EventHandler;
import org.bukkit.event.Listener;
import org.bukkit.event.block.BlockBreakEvent;
import org.bukkit.event.block.BlockPlaceEvent;
import org.bukkit.inventory.ItemStack;
import org.bukkit.plugin.java.JavaPlugin;

public class PickYoSpawner extends JavaPlugin implements Listener {

	@Override
	public void onEnable() {
		getServer().getPluginManager().registerEvents(this, this);
	}

	@EventHandler
	public void onBlockBreak(final BlockBreakEvent event) {
		if (event.getBlock().getType() == Material.MOB_SPAWNER) {
			final boolean cancelled = !event.getPlayer().getName().equals(
					getConfig().getString(toString(event.getBlock().getLocation()), null))
					&& !event.getPlayer().hasPermission("pickyospawner.all");
			if (!cancelled) {
				getConfig().set(toString(event.getBlock().getLocation()), null);
				event.getBlock().getWorld().dropItemNaturally(event.getBlock().getLocation(),
						new ItemStack(Material.MOB_SPAWNER));
			}
			saveConfig();
			event.setCancelled(cancelled);
		}
	}

	@EventHandler
	public void onBlockPlace(final BlockPlaceEvent event) {
		if (event.getBlock().getType() == Material.MOB_SPAWNER) {
			getConfig().set(toString(event.getBlock().getLocation()),
					event.getPlayer().getName());
			saveConfig();
		}
	}

	private String toString(final Location location) {
		return location.getWorld().getName() + "_" + location.getBlockX() + "_"
				+ location.getBlockY() + "_" + location.getBlockZ();
	}
}