Rather than telling you how to use KPPP, I'll explain how I connect using this phone using PPPD and CHAT with a GPRS or UMTS device.
(note, this is a packet switched connection, not literally a circuit switched connection so your mileage may vary)
Step 1:
Verify that data service provided by your wireless carrier works from the handset directly(ie, you can connect to some web site using the phone's browser)
Step 2:
Plug the phone into the USB cable and the cable into the computer's USB port.
Step 3:
Verify that the device is detected. On my system I check for /dev/ttyACM0 (note, this may be different with your type of phone and cable)
Step 4:
Create a link between the USB device, in my example /dev/ttyACM0 to /dev/modem (note, this step is usually option, but required if you're using KPPP)
Step 5:
In my example, I create a CHAT script in the directory /etc/ppp/peers/ titled
gprs-connection
and enter the following code:
Code:
/dev/modem
lcp-echo-failure 0
lcp-echo-interval 0
nodetach
connect "/usr/sbin/chat -v -t3 -f /etc/ppp/peers/gprs-chat"
nocrtscts
local
noipdefault
ipcp-accept-local
defaultroute
novj
nobsdcomp
novjccomp
nopcomp
noaccomp
persist
maxfail 99
Step 6:
Now we'll create the
gprs-chat file referenced above in the
gprs-connection script. Paste this in the file /etc/ppp/peers/gprs-chat:
Code:
'' AT
OK AT+CGDCONT=1,"IP","proxy"
OK ATD*99#
CONNECT ''
Step 7:
Connect to GPRS using the command
Code:
/usr/sbin/pppd call gprs-connection
Now, the script created here is specifically for the GPRS/EDGE/UMTS(WCDMA) network(s) I support.
There are several possible variables that can and will probably need to be changed to work with your carrier's network.
Specifically take notice of:
OK AT+CGDCONT=1,"IP","proxy"
This AT command intialiases the modem and tells it to use the "IP" protocol and the Access Point Name(APN) "proxy". You will have to change the APN "proxy" with whatever APN your service is provisioned with. Again, not knowing which carrier you are using I don't know which APN's are used or if your carrier requires something else entirely(give me the phone and cable for a few minutes and I can probably figure it out though

)
I have used this or a slightly modified script to connect with several types of devices, I have experienced some devices however who do not work properly with CHAT and have used "wvdial" instead to accomplish the same thing.
If you want to tether using another interface such as bluetooth or IrDA or serial, replace the symbolic link to /dev/modem with /dev/rfcomm0(bluetooth) or /dev/ircomm0(ir), etc.
If you have any questions, feel free to let me know and I will help you as best I can.