Thanks for the fast answer, unfortunately having a second "graphic adapter" is a way I do not want to pursue, also because:
"Note: This release does not support OpenGL acceleration (3D hardware acceleration) so therefore applications and features that require OpenGL, Quartz Extreme, Quartz Composer and other framework based on OpenGL will not be fully supported. Examples of such features are Keynote Presentations, iPhoto Slideshows and iMovie."
Does it means that the mini displayport does not permit to run two different monitors?
Thanks.
MB