
I think the original poster meant opening the mouse, not just
releasing the ball and getting to the rollers. I found that on the
original ADB mouse, sometimes unscrewing the two halves allowed for
easier cleaning.

If the original poster has his answer, I'll ask: How do you open the
new ergonomic mouse? By open, I mean split the two halves to get at
the guts. It isn't obvious to me based on the 5 minute look I spent
with one at the office yesterday as there are no visible screw
heads.