Prb de connex modem iam 3G

Bonjour,

j'ai un modem iam 3G huawei mobile broadband

je viens d'installer ubuntu 10.10, apres j'ai installer mn wvdial et enregistrer mn qvdial.conf.
mais quand je lance wvdial iam dans la console, je reçois ce message :

--> WvDial: Internet dialer version 1.60
--> Cannot get information for serial port.
--> Initializing modem.
--> Sending: ATZ
OK
--> Sending: ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
ATQ0 V1 E1 S0=0 &C1 &D2 +FCLASS=0
OK
--> Sending: AT+CGDCONT=1,"ip","www.iamgprs1.ma";
AT+CGDCONT=1,"ip","www.iamgprs1.ma";
OK
--> Modem initialized.
--> Sending: ATDT*99#
--> Waiting for carrier.
ATDT*99#
CONNECT
--> Carrier detected. Starting PPP immediately.
--> Starting pppd at Fri Apr 22 22:26:46 2011
--> Pid of pppd: 1575
--> Using interface ppp0
--> pppd: ([18]?[08]?[15]?[08]
--> pppd: ([18]?[08]?[15]?[08]
--> pppd: ([18]?[08]?[15]?[08]
--> pppd: ([18]?[08]?[15]?[08]
--> pppd: ([18]?[08]?[15]?[08]
--> pppd: ([18]?[08]?[15]?[08]
--> Disconnecting at Fri Apr 22 22:26:48 2011
--> The PPP daemon has died: A modem hung up the phone (exit code = 16)
--> man pppd explains pppd error codes in more detail.
--> Try again and look into /var/log/messages and the wvdial and pppd man pages for more information.
--> Auto Reconnect will be attempted in 5 seconds
--> Cannot get information for serial port.


et ca se repete.
merci d'avance pr vos suggestion