I use a Huawei E160E HSDPA USB stick with Slackware as detailed here.
http://www.linuxquestions.org/questi...4/#post4213848
You would need to modify the chat script to change the APN and perhaps add lines if you need user and password to connect.
I just keep the pppd line in a little script that I run as root after plugging the modem and allowing time for the device to be detected and usb_modeswitch to do it's stuff.
At the end of a session I do, as root, 'pkill pppd' then unplug the modem.