bin/185976: release building fails with missing 'unbound' user error (releng/10.0)

[remko at FreeBSD.org]

Synopsis: release building fails with missing 'unbound' user error (releng/10.0)

Responsible-Changed-From-To: freebsd-i386->re
Responsible-Changed-By: remko
Responsible-Changed-When: Fri Jan 24 08:18:34 UTC 2014
Responsible-Changed-Why: 
Dear Release Engineers, can you tell the submitter whether or not the host build environment is
required to be on a certain version because of the missing user?

http://www.freebsd.org/cgi/query-pr.cgi?pr=185976