return codes standardized?

Hi,

I've seen that the POSIX test in the samba build farm fails on some non-Linux
platforms. One of the reasons is that different OSes return different errnos on
posix open calls on symlinks. The torture test expects to receive
NT_STATUS_OBJECT_PATH_NOT_FOUND from the server but the return codes of other
Unixes are mapped to different NT status codes. I wonder where is defined that
NT_STATUS_OBJECT_PATH_NOT_FOUND is the right bit that we should return on a
posix open on a symlink. Do we have an RFC draft or anything like that which
covers this?

Cheers
Björn