I have an O2 UMTS stick, which works quite nicely with Linux and sometimes even with Windows.
lsusb ... Bus 008 Device 005: ID 12d1:1003 Huawei Technologies Co., Ltd. E220 HSDPA Modem / E270 HSDPA/HSUPA Modem ...
I just installed umtsmon and it worked right away.
Sometimes it gets confused with the usb disk part on the stick. If this is the case, I remove all usb kernel modules and reboot the machine. In general it seems to be a problem with usb_storage module but I could not figure out where the problem really comes from.
Under Windows Vista the software on the usb stick is not really easy to install and the stick only works in the slot where it was installed in.
To get the software working do the following:
If this does not work or if there no broken devices, follow these steps:
After these steps, the modem devices should show up in the device manager.