setfacl and mtime

Hi,

I've been toying with ACLs lately, and I noticed that ACL operations change
the mtime of the file, whereas chmod does not. Is this functionality
intentional? More importantly, can it be turned off?

craig_at_burnout<~> touch me && ls -l me && sleep 300 && setfacl -m u:root:rwx
me && ls -l me
-rw-r--r--  1 craig  admins  0 May 19 03:09 me
-rw-rwxr--+ 1 craig  admins  0 May 19 03:14 me*
craig_at_burnout<~> rm me
craig_at_burnout<~> touch me && ls -l me && sleep 300 && chmod 777 me && ls -l
me
-rw-r--r--  1 craig  admins  0 May 19 03:28 me
-rwxrwxrwx  1 craig  admins  0 May 19 03:28 me*
craig_at_burnout<~>

-Craig