Linuxcare: Configuring Your Mouse For Linux

“Recently a customer called to report that his mouse wasn’t
working. I asked for some details about the system and quickly
found out that he had a Microsoft IntelliMouse. “Aha!” I said, “you
need to change the name of your mouse driver from ‘PS/2’ to
‘IMPS/2’ in your XF86Config file.”

“The IntelliMouse is an example of a style of mice, originally
popularized by Microsoft, which have a wheel in place of the middle
button. These are also called ZAxis mice, and allow the user (at
least under Windows) to perform scrolling operations by turning the
wheel. But they need a special driver; I’ve seen other cases where
an IntelliMouse didn’t work properly because people were using the
generic PS/2 mouse driver instead of the new IntelliMouse PS/2

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