If you gave knc your btc address, they usually set it up for you mining at eligius with your btc address. You probably mined like that until you had set up the miner to your own pool choices.
Hmm, now that sounds like a very reasonable explanation. I was under the impression that they mined for me on their own pool not Eligius; and yes I did give them my btc address. Ok, that explains it. I just wasn't aware of them using Eligius.