I have tested this on two different intel machines running RedHat Linux 6.1. I have chosen a 2 button Microsoft Intellimouse (PS/2) during the installation of RedHat. Later after the installation I ran Xconfigurator. Everything goes as it should until it is time to click on the button that lets Xconfigurator know I can see the new screen set up correctly. The screen looks great, however, the mouse never can be moved over the button. The mouse pointer is also jumpy as I move the mouse around. After I re-installed Redhat and have chosen a generic 2 button (PS/2) mouse, Xconfigurator works as it should.
I believe this to be fixed with 6.2