The Wii mote does not emit IR.... it has a built in IR camera.
If you want to set up something for this home brew client ... it won't be on the s-70 but if you follow the link below you may be able to do a "Minority Report like" interface which they may enjoy .... a lot more work then it would be worth IMO though.
If you want to learn more Wii-mote hacks here is a good place to start:
[Link: johnnylee.net]