3g connection problem

majil
I'm having trouble connecting my board to internet using a USB 3G Modem in
3G mode (I managed to connect using gprs mode) 
I can see there is two application in the board. 3g-ppp and 3g-modem
3g-ppp is a script which calls for 3g-modem binary so you have to call
3g-ppp. I did but I got this :

[root@FriendlyARM /]# 3g-ppp
>>> The usb device in modem mode. <<<
>>> this modem no target vid and target pid <<<
Error: Could not find file -W


This is inside of 3g-ppp script:


#!/bin/sh

#----------------------------------------------

CONFIGFILE=$1
SWITCHMODEM=0
chat -v TIMEOUT 3 -f /etc/ppp/peers/chat-testmodem < /dev/ttyUSB0 >
/dev/ttyUSB0
if [ $? -ne 0 ]; then
    3g-modem -c $1 -W
    SWITCHMODEM=1
else
    echo ">>> The usb device in modem mode. <<<"
#   strlen( /etc/3g-modem/xxxx.xxxx.xxxx.xxxx ) = 33
    if [ ${#CONFIGFILE} -lt "33" ]; then
        echo ">>> this modem no target vid and target pid <<<"
        3g-modem -c $1 -W
        SWITCHMODEM=1
    fi
fi


#----------------------------------------------

[ ${SWITCHMODEM} -ne 0 ] && sleep 8


in /etc/3g-modem directory there are some file with names like vid.pid.ff
and etc but I don't know if I'm supposed to make a new file for my USB 3G
Modem or not. 
Could you help me with the 3g-ppp script see what its problem is?