No problem: Just copy your original 3.x x-surf.device to the Devs:Networks/ path and you`re ready to surf the Net ;-) I hope you`ll enjoy the OS4 , and give us feedback from your experience :-)
P.S. My experience from the OS4 ETH use is an ultra-fast data transfer (compared to the 3.x one), but I`ve noticed strange and unpredictable lockups during the SMB-volumes mounting or file copy from and to these volumes... (might be the WinXP-side the culprit, but from the 3.x side I`ve never experienced such strange behaviour)