Bingo, that worked fine, and in fact I got email from GT Interactive that confessed that safedisc (the copy protection scheme causing this problem) doesn't work with UDMA66 controllers. I had my CD plugged into a Promise UDMA66 controller add-on card. Interestingly enough, GT Interactive then proceeded to point me to the above-referenced patch on gamecopyworld!
I have asked them what happens when the next UT patch comes out, no answer yet...