The Samsung Charge is the must frustrating droid I have every worked with. Every kernal. ROM flash seems to be buggy. Anyways to get wifi tether working for root users:
1) Download Android Wifi Tether (I used 3.1 beta9)
2) Place on SDcard and install
3) Turn on WiFi (okay if no networks in range)
4) Open Wifi Tether
– On the first boot, go to settings and select the Samsung Fascinate as the phone
5) Start the tether.
– If it’s work you will see the Green download/red upload numbers
– If you don’t restart
– If you stop the tether you will need to restart before connecting to wifi or tethering again (sorry, it’s an unsupported phone, just be happy it works)