debugging/tracing a setuid program

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

I have an interesting problem: How do you debug or ktrace a setuid binary 
that exhibits the problem only when run as non-root?

(Specifically, this is sudo built for NetBSD-6 via kver in a chroot on -8 
failing to read the timestamp files on real -6. When called as root, it 
doesn't use the timestamps.)