Despite what some vendors say (like the ColorVison Spyder folks), it is now possible to calibrate both monitors under MS windows. The secret is to download Microsoft's Color Control Panel Applet powertoy. The use a Spyder or what ever to calibrate each monitor. Make separate profiles. Then use the Color CP Applet to assign the correct profile to the correct monitor. Don't use the profile loader that comes with the calibrator (like OptiCal). Instead put the Color CP Applet in your Start -> Programs -> Startup folder and give it the L command line parameter.
One note, your video must have two LUTs (forgot the meaning) in order to allow both monitors to be calibrated at the same time.
I hope this helps,
Just having fun with my cams: