Derek Peschel wrote:

> NetBSD support of all five buttons (X only says it supports three and I
>   have been unable to get debugging messages out of the ums driver)

I'm pretty sure NetBSD will support all five buttons.  What you do with
them in X is another matter.   An easy way to test the mouse is to try
`od -X /dev/wsmouse' when you have a console.

    -- Lennart