I made several tries with USB dongle but I did not suceed with messages like "Volume files not compatible or empty sd card:.." So In order to connect a 3G network when no WiFi is available I bought a WiFi mobile router Huawey E5830 and works very well. Simply insert your SIM and provides a WiFi access up to 5 devices.
Hope it helps although the question still is open
¿Does anyone how to cobnbtrol USB port from Androdi 2.2 to let recognize othe usb devices like Bluetooth for GPS or any other rather than external disk ?
Enviado desde mi zt180 usando Android Tablet Forum