What you're talking about doing is called bridging, and no, the MS box won't do that for you. There are dedicated wireless bridge devices, and some wireless routers that will act as bridges, but Microsoft never made any.
Look at Netgear, D-Link, and Linksys for "wireless bridge" devices. Also look at their routers to see which ones offer bridging mode. You can also search this forum for "bridge" and see what pops up.