I running Kurumin (a Brazilian flavor of knoppix) and have no problems to reach the web.

If I try the knoppix cd I get the same error you get. If I swicht back to kurumin cd i do get the connection.

I printed in paper both kurumin and knoppix pppoeconf, put the paper side by side and compared line by line. They are identical.

I should help if we (me and Julian) could understand how a dsl connection is got under knoppix. Which steps are done.

I do intend to install Knoppix in my hd but I can not do it before I figure how to connect at internet. I completely gave up on windows.