I'm just playing with remote kernel debugging on
a 68040 board. (from an Ultrix host)
gdb (even the version in the NetBSD souce tree,
from a look at the source) uses trap #1 for
breakpoints on remote targets.
The NetBSD ports, as far as I can see, assume
sigreturn() there and use trap #15 for breakpoints.
How could this ever work? Or am I missing
something?
(After I changed it, breakpoints didn't cause
panics anymore.)

best regards
Matthias