I've built a 1.3.1 binary release built for the pmax but AFAIK, 1.3.1
is not yet officially out the door.

Plus, there is currently no space on ftp.netbsd.org, or I would
release the binary I have as an unofficial `1.3.1_BETA' snapshot.

The specific problem here is that the original `hockey-puck'mice
sold and shipped with DECstations 3100s work fine.  The problem is
that the newer, "square" mice (e.g,. from TC machines) take slightly
longer to initialize, and with a more accurate DELAY() in 1.3, the
 don't wait quite long enough for the newer mice.  That's fixed in 1.3.1.

I've created ~ftp/pub/NetBSD/arch/pmax/NetBSD-1.3.1_BETA on
ftp.netbsd.org as a 1.3.1 "snapshot", and placed precoompiled 1.3.1
pmax kernels there inside the binary/kernel/ subdirectory.

It's safte to install 1.3, and then fetch and copy in the 1.3.1
kernel by hand.  (The file you want is probably netbsd.aout.)

Followups on this  should probably go only to port-pmax, please.