I had the same problem (with a totally different mouse) under Ubuntu and Vector Linux (and probably would with Gentoo too). In both cases, I needed to edit the "xorg.conf" file so the protocol for the mouse was "microsoft" (it kept getting detected as "serial" in installation I believe). I'd advise backing it up first, and revert to the original if this doesn't work (not that it'd be dangerous- you just might forget the original protocol if it turns out to be correct). I haven't had a working Linux distro around for a while, so I'm afraid I can't test it
Of course, your mouse may not be that protocol, I'm just speaking from my experience of when a mouse's protocol didn't get properly detected and configured.
Hope that helps
