DVI Panel won't "go to sleep" with T43 & Dock

[JHaislet]

I just got a Dell 2405 FPW hooked up thru the Dock II with the T43. Through the "Display Properties" in XP, I've got the monitor set to power off after 3 minutes, yet when the three minutes is up, the screen flashes & the monitor stays on.

Any ideas?

Update: It was the dang MS Wireless Intellimost Explore. Evidently, something is broken with it as it's constantly in motion (not noticable though) which is keeping the screen from turning off. Everything goes to sleep fine with a corded mouse plugged in.