Here is a thread from a couple of months back that addressed the brake squeal/noise. I would try the suggestions specified and see if that may solve your noise issue. Check out Nick's advice about "burnishing" and mine about doing some "hard" stops. "Stop and Go" city driving will cause the squeal to occur in a matter of hours. You need to really get on the brakes to get the glaze off the rotors.
http://www.cadillacforums.com/forums...ke-squeal.html