b00 y44. Login in to the ADC (free membership available), download the ZFS Beta1 seed, install on to your new Leopard install, and reboot… 2 minutes total and you get what you desire:

Macintosh:~ tamr$ sudo zpool 
Password:
missing command
usage: zpool command args ...
where 'command' is one of the following:

	create  [-fn] [-R root] [-m mountpoint]   ...
	destroy [-f] 

	add [-fn]   ...
	remove  

	list [-H] [-o field[,field]*] [pool] ...
	iostat [-v] [pool] ... [interval [count]]
	status [-vx] [pool] ...

	online   ...
	offline [-t]   ...
	clear  [device]

	attach [-f]   
	detach  
	replace [-f]   [new_device]

	scrub [-s]  ...

	import [-d dir] [-D]
	import [-d dir] [-D] [-f] [-o opts] [-R root] -a
	import [-d dir] [-D] [-f] [-o opts] [-R root ]  [newpool]
	export [-f]  ...
	upgrade
	upgrade -v
	upgrade <-a | pool>

	history []
	get   ...
	set