Whoops, sorry about my previous message. I got distracted and
hit the send button too early. :-)

Arnaud Blanchard wrote:

> 1/ Where is the 3button mouse emmulation
>    In the kernel ( where ?), or in Xmacbsd ( Xserver)

It depends. It really is a little of both. The kernel
does some "remapping" of mouse and keyboard presses, 
depending on the type of mouse. But the Xserver, using
xmodmap, can also do similar remappings.

	--John