Darn, I updated the system and the same problem has re-appeared with the second monitor.
Here's the original thread.
http://forums.creativecow.net/thread/124/868971#868971Primary System Info -
Mac Pro 2x3.2 Quadcore - 10.5.6 - QT 7.5.5 - 14 GB RAM - nvidia8800GT - SATA internal & external storage - Blackmagic Multibridge Pro (v6.7)- Open GL 1.5.9 - Wacom Intous2 tablet