After giving it a little more thought, I may be able to help? When I installed RedHat on my IBM X22, I was not able to use the scroll function on the external USB mouse. The other problem was that when I disconnected the mouse, the thinkpad trackpoint did not function.
I solved the problem by installed RedHat without the mouse attached. Then after installation, connected the USB mouse and everything worked perfectly! The scroll function on the external mouse and the trackpoint also.