kqueue NOTE_LINK

Hi,

I'm not sure if this is a bug or a documentation problem or
a feature.

I am playing with kqueue and on NetBSD 3.99.21 it seems to
return 
NOTE_LINK event on directory if I unsuccessfully (EPERM [1])
try to make 
a hardlink to this directory. This seems to disagree with
manual [2]. 
What's wrong?

Thanks,

r.

[1] ln(1):
``Hard links may not normally refer to directories and may
not span file 
systems.''

[2] kqueue(2):
``NOTE_LINK      The link count on the file changed.''

kern/34267