Installation of a cutting edge stuff on Linux machine is always challenging and enforce you to look onto the non-UI part of the picture. I dont know why majority of the IT people like windows, if they are not working on .net!! BTW Last weekend i successfully installed Huawei e156g USB modem on Ubuntu 10.04. Here are the steps:

Step-1 : Open /etc/wvdial.conf in gedit-

sudo gedit /etc/wvdial.conf

if you dont have wvdial installed on your system run:

sudo apt-get install wvdial

Step-2: Replace the text of wvdial.conf (I did for BSNL) with the following:

[Dialer Defaults]
Modem Type = Analog Modem
Phone = *99#
ISDN = 0
Baud = 460800
Username = " "
Password = " "
Modem = /dev/ttyUSB0
Init1 = ATZ
Init2 = at+cgdcont=1,"ip","bsnlnet"
Stupid Mode = 1

Save the file. If it cry for permissions run :

sudo chmod 777 /etc/wvdial.conf

Step-3 : Create a new file in /etc/udev/rules.d and rename it to ’15-huawei-e1550.rules’. Copy and paste following line to this file and save:

SUBSYSTEM=="usb",
SYSFS{idProduct}=="1446",
SYSFS{idVendor}=="12d1",
RUN+="/lib/udev/modem-modeswitch --vendor 0x12d1 --product 0x1446 --type option-zerocd"

Step-4 : I dont think restart is needed, (but as i did) restart the system.

Step-5 : Connect your Huawei USB modem device and wait till icon appears on desktop.

Step-6 : Right click on icon and select ‘Eject’ option.

Step-7 : Open terminal and run

wvdial

Output will show you IP information and now you are all set to browse the web. :)