By default, if you connect USB modem that will work in Ubuntu without any issues. If not you may need to install usb_modeswitch and wvdial packages . For that you need the connect script of the modem and vendor id etc...

Even me too facing the same problem

buddy try this.

plug micromax and go for option usb tethering or hotspot active probabaly it will start working..:)

bet of luck.

I hope it's not too late to post this since it's a month since this thread was created. I've had a similar problem but I use Kubuntu 12.04. Normally, when you plug in a usb modem(or also known as "dongle") it should just be configured automatically, or I don't know the jitter-jatter behind it. But I got it to work! This is what I did. Note that we don't have the same hardware so the output might be different from what your machine will show. So:

First, plug in your USB modem. Then pull up a terminal and run lsusb.

$ lsusb

It should show you the usb devices currently in use or are active/plugged in.

You should have similar(not so) output like this:

Bus 002 Device 002: ID 0603:00f2 Novatek Microelectronics Corp.
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 006: ID 1c9a:6061 Omega Technologies Co., Ltd.
Bus 001 Device 003: ID 059b:047a Iomega Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub

The line:

Bus 001 Device 006: ID 1c9a:6061 Omega Technologies Co., Ltd.

is what you're looking for. This is the device info of your USB modem. But you only need the device ID, which in my case the device ID of my USB modem is 1c9e:6061. As I have said, we don't have the same hardware so yours might have a different device name(such as Huawei or something..) and different device ID. Note it down if you want.

Now we have to make it load its drivers. To do that you must log in as root as follows:

$ sudo su

Then run:

$ modprobe option

Now if you check /sys you'll have a path like this:

/sys/bus/usb-serial/drivers/option1/new_id

Now enter the device ID of your USB modem to option1. Mine is 1c9a:6061. So replace this ID to what your USB modem ID is. Run:

$ echo 1C9A 6061 > /sys/bus/usb-serial/drivers/option1/new_id

Now, you're halfway there.. oh, wait a few minutes.. check your connection manager. Boom! Create your profile and you're good to go.

Now if you reboot your machine and plug in your USB modem again you'll find that it won't get recognized again. Run those commands again or make a script. So that everytime you want to use your USB modem after a reboot just run that script and you'll be surfing the net. I haven't found a workaround on how to do that as soon as the system is up or you can just place that script in the startup application.

I think that's about it. So, yeah..

-jds