Upgraded Mac Pro, now purchased iTunes HD movies won't play

I just upgraded my Mac Pro (2006) to a Mac Pro (2008) so it would be a little faster, be Mountain Lion compliant, etc. The new Mac Pro has an ATI Radeon HD 5770 and I am continuing to use my 30" Cinema display.

Now when I try to watch a purchased iTunes movie or TV show that I had previously purchased on my old Mac Pro, I get the "This movie can be played only on displays that support HDCP (High-bandwidth Digital Content Protection)" message. When I look at the show listing in iTunes, thay have the joint HD-SD emblem, so they should be able to be played in the lower resolution, correct?

I can't believe that with all of the apple products and media I have purchased, everything 100% apple, I am no longer able to watch apple movies!

Any suggestions?

Thanks

jmac