So you work for Microsoft, eh? Should have noticed that at first.
The Logitech Mouse driver works well with many configurations.
http://www.apple.com/downloads/macosx/drivers/
OR ust the IOKit to make your own drivers if you have a specific need:
http://developer.apple.com/documentation/DeviceDrivers/Conceptual/IOKitFundamentals
yeah, and I should have noticed you work for the local board of education with great insights like that.