I have know idea if this will work or not, but I have found this on a few different forum all posted by Diyism, so if it does work he deserves all the credit.
My android os is CyanogenMod 188.8.131.52,
1.Enable "Settings\Wireless controls\Internet tethering"
2.Install HTC Remote NDIS based Device driver(http://forum.xda-developers.com/atta...2&d=1265356413)
3.Set the HTC adapter as: IP:192.168.2.1, Mask:255.255.255.0
4.Set the PC ethercard as shared connection
5.Run these codes in terminal:
ifconfig usb0 192.168.2.2 netmask 255.255.255.0
busybox route delete default
iptables -F -t nat
busybox route add default gw 192.168.2.1
setprop net.dns1 184.108.40.206
setprop "net.gprs.http-proxy" ""
6.Now your g1 could open browser to view any web pages on the internet, and update apps in the Market.