Although this writeup is based on setting it up on Ubuntu Intrepid, the following steps should be applicable to other distributions as well.  You may want to improve on these steps by placing these commands on a bash script, but what I’m giving you is the staightforward way of doing it.

Here are the steps:

Download the usb_modeswitch binaries and the latest usb_modeswitch.conf file here:

http://www.draisberghof.de/usb_modeswitch/#download

Extract the usb_modeswitch binary and place it in a place like /usr/sbin.  usb_modeswitch.conf goes to the /etc folder. Comment out the lines which has the headers Alcatel OT-X020.  You have to disable the other modem enabled on this config file, or usb_modeswitch won’t work.

Edit your wvdial.conf file (located in /etc) to look like this (As a bonus, I added a default dialer section for your nokia cellphone – I have a Nokia E61i to connect to the smart internet network):

[Dialer Defaults]
Init1 = ATZ
Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Init3 = AT+CGDCONT=1,"IP","internet"
Modem Type = USB Modem
ISDN = 0
Phone = *99#
Modem = /dev/ttyACM0
New PPPD = yes
Baud = 460800
Idle Seconds = 3000
Auto DNS = 1
Stupid Mode = 1
Compuserve = 0
Dial Command = ATDT
Ask Password = 0
FlowControl = NOFLOW

[Dialer smartbro]
Init1 = ATZ
#Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Init2 = ATE1
#Init2 = ATE0V1&D2&C1S0=0
#Init3 = at_opsys=0
#Init2 = ATQ0 V1 E1 S0=0 &C1 &D2
Init3 = AT+CGDCONT=1,"IP","smartbro","",0,0
Modem Type = USB Modem
ISDN = 0
Phone = *99#
Modem = /dev/ttyUSB0
New PPPD = yes
Baud = 912600
Idle Seconds = 3000
Auto DNS = 1
Stupid Mode = 1
Compuserve = 0
Dial Command = ATD
Ask Password = 0
FlowControl = NOFLOW

Write down this code and save it as initmodem.sh and place it in /usr/sbin:

#!/bin/sh
modprobe usbserial vendor=0x1c9e product=0×6061 && usb_modeswitch
sleep 3

Plug in your SmartBro USB dongle and run:
# sudo /usr/sbin/initmodem

To connect to the internet, just type in:
# sudo wvdial smartbro

and to disconnect, just press CTRL+C, or kill the pppd process

I think this should work also with SmartBro 1500 as well.  Enjoy your smartbro connection!