Hi, just had the same problem as you and thanks to the good support dude i was directed to when i called my ISP i think i can give you the answer to this question.

The problem is at this knoppix or pump or whatever tries to request two ip's at the same time. This would lead to a conflict if you're having a finite set of IP's to get from your ISP. So you're getting none.

I tried "pump -i eth0" while talking with him on the phone and he said "ok, now youre requested two ip's i see". I was like "huh, no? just one". and after a little forth and back we drawed the conclusion that it must be my DHCP request thats a little fucked. Maybe its just a conf file in linux that does this, i dunno know. Just tried knoppix a few days ago and the brain stumbling, headatache began. Im so happy that i now is back on the net and hopefully everyone with the same problem can learn from this experience.

So the thing you should do is call your ISP and tell them to release your IP's and boot up in another OS or fix the bug/misbehaviour of knoppix's DHCP request of two IP's.