The Huawei E220/E270 stick I got from my mobile provider is working on Ubuntu Lucid Lynx out-of-the-box.
The mobile provider was pre-configured in the provider database of the Network Manager and there was no need for a special setup of the USB stick.
The latter was necessary on my Dell notebook (see
usb-modeswitch), but not
here on the PowerPC architecture in the iBook G4.