archvile

Upon trying to install Sonar 2.0 XL on my Windows XP PC, it promptly tells me that I don't have Direct X 8.1 installed, which is right, I have Direct X 9. The problem is that I can't go any further until it thinks I have Direct X 8.1. Is there a work-around for this or a program that will make a program think that you have a different version of Direct X installed? Any help on this matter would be great, because Sonar 2 XL is too expensive to go to waste. Thanks in advance.