I don't know if a driver for your modem is included with Knoppix or not- a search for 'alcatel' turned up nothing but a quick google got me this:
http://linux-usb.sourceforge.net/SpeedTouch/
Perhaps it will be of some assistance. I was wondering if Alcatel ever fixed the multitude of vulnerabilities I read about a few years back. As I recall they were so bad that it was quite a risk to use one- hopefully they've gotten them fixed.