i use a mac pro 3.1 (early 2008) with an ATI HD 5770 Graphic Card and two Samsung Syncmaster 226BW Displays.
Evrything works perfect, except i only can use on ColorSync Profile.

1 Display is connected directly to the Graphics Card DVI Output, the other with a miniDisplayPort to DVI Adapter.
when i choose a color Profile on the left Display, the same Profile will be set to the other and vice versa.

also only one Display really seams to use (Change) to this color Profile.

Im also not in Mirror Mode ;-)

The Systemprofiler shows me both of my Displays under the Graphic Card Tab, but in ColorSync there is only one Syncmaster Display listet.

i have no more ideas, searched the web, bought a DataColor Spyder4 Pro and calibrated both Monitors.
In the End, Mountain Lion only use on Profile for both Displays.

I also have changed the miniDisplayPort to DVI Adapter and all Cables with no result.

Please, any Ideas ?

Btw. under Snow Leopard evrything with the same System worked well, the Problem exist since Mountain Lion !