hey, first of all thanx to the ones who replied the message!
I still have the same problem though.... First I tried what mzilikazi, but when I did pump I got "operation failed", and when I tried ping, i got the message "unknown host".
Then I tried what shah told me. I didn't know how to find my i.s.p. nameserver, so on windows I tried ipconfig /all and I got two DNS servers (200.43.32.12 and 200.43.32.13), so i figured those were the i.s.p. nameservers. Then I went back to Knoppix (I'm running it from the CD), and I edited the file /etc/resolv.conf four times, and after each time I tried pump and got "operation failed" each time, I also tried netcardconfig and got the same message, and I also tried to open a web page with the web browser and it didn't work.
The way I changed the file was this:

First time:
# Insert nameservers here
# nameserver 127.0.0.1
nameserver 200.43.32.12

Second time:
# Insert nameservers here
# nameserver 127.0.0.1
search cantv.net
nameserver 200.43.32.12

Third time:
# Insert nameservers here
# nameserver 127.0.0.1
search cantv.net
nameserver 200.43.32.12
nameserver 200.43.32.13

Fourth time:
# Insert nameservers here
# nameserver 127.0.0.1
200.43.32.12


I don't know if that was the way I was supposed to edit the file, or if I'm doing something wrong, or not doing something, but I still can't connect to the internet! HELP!!!