I removed it with kidokiller.exe from Kaspersky. Now Clamwin works again. I am also applying a W2000 SP 4 that prevents the usage of this security leak. I think I should have done that before. That was a mistake, not checking if the latest SP was installed. I presumed it was... Well lesson learnt.

So far as I searched SP 4 is the latest update there was for W2000. If somebody knows otherwise, please inform me.