Getting multi-mode usb modems working on Linux is still a challenge. After reading many articles in the internet, I manage to get BandLuxe C120 HSDPA modem working on Kubuntu 9.10. This should work on Ubuntu as well.
This blog entry actually provide me with all the information.
http://my.opera.com/CrazyTerabyte/blog/2008/12/28/bandluxe-c120-3g-modem-from-oi-velox-plug
The installer for Linux is available at;
http://www.bandrich.com/Download_C120-3a.html
Use the Eee PC driver not the Linux driver.
However, I couldn't use the option.ko in the package since the kernel version is different. I tried with the options.ko which comes with Kubuntu 9.10 and it did work for me :).
Here is the modified installation script which you can use, such that the installer will not override the original option.ko driver. So we only use the udev rules which will stop mounting this device a storage device and only use it as a usb modem.
############################################################################
#!/bin/sh
MODDIR=/lib/modules/`uname -r`
echo "Backup file modules.alias"
cp -v ${MODDIR}/modules.alias ./modules-original.alias
echo "Patching file modules.alias"
sed -f vidpid.sed ./modules-original.alias > ${MODDIR}/modules.alias
echo "Unload the kernel module"
/sbin/rmmod option
echo "Rules for auto switch from CDROM to Modem"
cp -vf 10-bandluxe.rules /etc/udev/rules.d/10-bandluxe.rules
mkdir -p /usr/share/hal/fdi/preprobe/20thirdparty/
cp -vf bandluxe.fdi /usr/share/hal/fdi/preprobe/20thirdparty/bandluxe.fdi
##########################################################################
Good luck!
