Well, my Logitech Cordless Optical Trackman is working flawlessly under 10.6.3 after installing a new battery. You must have also just recently updated your system to 10.6.3 since it just came out last week.
No doubt everyone here has already done so, but have you checked under System Preferences, Logitech Control Center to make sure the various settings are still correct? And that you are using the most recent software version?
Also, where do you have the Logitech USB RF receiver plugged in? Keyboard? Directly into computer? Into a hub, powered or non-powered? Could be a factor.
We can always hope the answers to our problems will be so simple.
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