2)Check ur nokia connection as it’s vendor and product number
[root@server1 ~]# lsusb
Bus 001 Device 001: ID 0000:0000
Bus 002 Device 004: ID 0421:0061 Nokia Mobile Phones
Bus 002 Device 003: ID 0e0f:0002
Bus 002 Device 001: ID 0000:0000

3)Add ur modem here with following command
[root@server1 ~]# sudo /sbin/modprobe usbserial vendor=0×421 product=0×061

4)add ur setting with following command
[root@server1 ~]# wvdialconf /etc/wvdial.conf
Scanning your serial ports for a modem.

ttyS0: ATQ0 V1 E1 — failed with 2400 baud, next try: 9600 baud
ttyS0: ATQ0 V1 E1 — failed with 9600 baud, next try: 115200 baud
ttyS0: ATQ0 V1 E1 — and failed too at 115200, giving up.
ttyS1: ATQ0 V1 E1 — failed with 2400 baud, next try: 9600 baud
ttyS1: ATQ0 V1 E1 — failed with 9600 baud, next try: 115200 baud
ttyS1: ATQ0 V1 E1 — and failed too at 115200, giving up.
Port Scan: S2 S3
WvModem: Cannot get information for serial port.
ttyACM0: ATQ0 V1 E1 — OK
ttyACM0: ATQ0 V1 E1 Z — OK
ttyACM0: ATQ0 V1 E1 S0=0 — OK
ttyACM0: ATQ0 V1 E1 S0=0 &C1 — OK
ttyACM0: ATQ0 V1 E1 S0=0 &C1 &D2 — OK
ttyACM0: ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0 — OK
ttyACM0: Modem Identifier: ATI — Nokia
ttyACM0: Speed 4800: AT — OK
ttyACM0: Speed 9600: AT — OK
ttyACM0: Speed 19200: AT — OK
ttyACM0: Speed 38400: AT — OK
ttyACM0: Speed 57600: AT — OK
ttyACM0: Speed 115200: AT — OK
ttyACM0: Speed 230400: AT — OK
ttyACM0: Speed 460800: AT — OK
ttyACM0: Max speed is 460800; that should be safe.
ttyACM0: ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0 — OK
WvModem: Cannot get information for serial port.
ttyUSB0: ATQ0 V1 E1 — failed with 2400 baud, next try: 9600 baud
ttyUSB0: ATQ0 V1 E1 — failed with 9600 baud, next try: 115200 baud
ttyUSB0: ATQ0 V1 E1 — and failed too at 115200, giving up.

Found an USB modem on /dev/ttyACM0.
Modem configuration written to /etc/wvdial.conf.
ttyACM0: Speed 460800; init “ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0″
[root@server1 ~]#
[root@server1 ~]# vim /etc/wvdial.conf
[root@server1 ~]# wvdial
–> WvDial: Internet dialer version 1.54.0
–> Cannot get information for serial port.
–> Initializing modem.
–> Sending: AT+CGDCONT=1,”IP”,”aircelgprs”,”",0,0
AT+CGDCONT=1,”IP”,”aircelgprs”,”",0,0
OK
–> Sending: ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
OK
–> Modem initialized.
–> Sending: ATDT*99#
–> Waiting for carrier.
ATDT*99#
CONNECT
~[7f]}#@!}!} } }2}#}$@#}!}$}%\}”}&} }*} } g}%~
–> Carrier detected. Starting PPP immediately.
–> Starting pppd at Sun Oct 4 03:25:12 2009
–> pid of pppd: 9507
–> Using interface ppp0
–> pppd: 60800
–> pppd: 60800
–> pppd: 60800
–> pppd: 60800
–> local IP address 10.183.117.164
–> pppd: 60800
–> remote IP address 10.6.6.6
–> pppd: 60800
–> primary DNS address 202.148.200.3
–> pppd: 60800
–> secondary DNS address 202.148.202.4
–> pppd: 60800
Caught signal #2! Attempting to exit gracefully…
–> Terminating on signal 15
–> pppd: 60800
–> Connect time 7.2 minutes.
–> pppd: 60800
–> pppd: 60800
–> pppd: 60800
–> Disconnecting at Sun Oct 4 03:32:23 2009

root@server1 proc]# cat /etc/wvdial.conf

[Dialer Defaults]
Modem = /dev/ttyACM0
Init1 = AT+CGDCONT=1,”IP”,”aircelgprs”,”",0,0
Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
Baud = 460800
#Init1 = ATZ
#Init2 = ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
ISDN = 0
Modem Type = USB Modem
; Phone =
; Username =
; Password =
Username = a
Password = a
Phone = *99#
Stupid Mode = 1

check the kppp pakage and start ur linux in graphic mode with startx

open kppp–>applications–>internet–>kppp
click on configure–>click account tab and click on new–>Manual setup–>dial–>connection name–aircel
clikc add–enter a phone no as put–>*99#–ok–>0k
click on Modems tab–>>New–>Modem name–/dev/ttyAMC0–>modem device–>select /dev/ttyAMC0
now click on Modem tab–>Modem commands–>
Initialization strings1=AT+CGDCONT=1,”IP”,”aircelgprs”,”",0,0
Initialization strings2=ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
click -ok
Query Modem to test it-
click ok and ok
put the user name=a
password = a
now connect ur aircel gprs properly

this for sanjay.
sanjay make changes according to your provider, its 100% works.
thank you.

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* c5-media:
file://media/CentOS_5.4_Final/repodata/repomd.xml: [Errno 5] OSError: [Errno 2] No such file or directory: ‘/CentOS_5.4_Final/repodata/repomd.xml’
Trying other mirror.
file:///media/CentOS/repodata/repomd.xml: [Errno 5] OSError: [Errno 2] No such file or directory: ‘/media/CentOS/repodata/repomd.xml’
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file:///media/cdrecorder/repodata/repomd.xml: [Errno 5] OSError: [Errno 2] No such file or directory: ‘/media/cdrecorder/repodata/repomd.xml’
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file:///media/cdrom/repodata/repomd.xml: [Errno 5] OSError: [Errno 2] No such file or directory: ‘/media/cdrom/repodata/repomd.xml’
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Error: Cannot retrieve repository metadata (repomd.xml) for repository: c5-media. Please verify its path and try again