Hmm, appears that you have linked to this very thread.
It should work fine. The wireless network for all the wifi devices connected to the router will drop down to b speeds (11mbit vs 56mbit). Note you'll get about half the speed of these nominal ratings in normal use as well. I think the encryption level you can use will also be limited. 802.11b can use WEP keys but I think that 802.11g can also use WPA.