There is a new release of lsof out which has a bug fix in
it for Linux with sparc64 kernels.
The previous version doesn't properly parse /proc/net/unix
(which has some 64-bit quantities in it) and thus fails
to map Unix-domain sockets to their names. Try running
lsof on an Ultra and notice that the lines corresponding
to Unix-domain sockets say:
gnome-ter 2709 jsergent 8u sock 0,0 10656
can't identify protocol
lsof 4.43, which just came out, has a tiny fix from me in
it that fixes this behavior, in dialects/linux/proc/dsock.c.
Upgrade (and your patch) is in lsof-4.43-1