su: pam_start failed

[Thomas Klausner <wiz%NetBSD.org@localhost>]

Hi!

I've created a new sandbox using pkgtools/mksandbox and it looks fine
AFAICT.

However, when I change inside and want to switch user to an
unprivileged one, I get

su: pam_start failed

without any further details.

ktracing it shows that it opens /etc/pam.d/su, then stats
/usr/lib/security/pam_rootok.so.4, then /etc/localtime and then it
wants to access /var/run/log multiple times, and fails because it
doesn't exist in the sandbox, and then exits.

'su -' fails the same way.

What could be the problem?

How can I get more details?
 Thomas