SP2, Wireless Zero Configuration, and older network adapters

After installing SP2 on all three computers in our home wireless (802.11b) network, the oldest computer (a Dimension 8200) began dropping the network connection after a short connect time.  After going through various disable/enable cycles and apparently waiting for some stars to align, it would then reconnect for awhile, then drop again, after a few minutes to an hour or so.  When this happens, a balloon message in the systray over the configuration icon says "A network cable is unplugged." 

 

The network adapter for this machine is ported to an older USB 1.1 that does not support Wireless Zero Configuration, but nevertheless it had a rock-solid, fast wireless connection to the router before SP2 was installed.  The router is an SMC7004AWBR, and the adapter is an SMC2662W, but not the latest version.  As far as I can tell, there are no later drivers available for my version of the adapter; there is more recent firmware for the router, but my other computers on the network (which do support WZC) are working fine, so I don't think that is the problem or solution.   I strongly suspect that if I uninstalled SP2, I would have a reliable connection again, but I would like to keep SP2 if possible, to facilitate future upgrades and because of the additional security on this machine, which is used by a teenager. 

 

My question for the board is: does anyone know if SP2 by default requires WZC support for wireless networks to function properly, and if so, are there options for a workaround here, short of going out and buying a new wireless adapter?  Thanks for any info or ideas.