Today a problem with a customer running Domino 8.5.2 on AIX 6.1 where the SMTP listeren task gave the following error:
05/22/2012 01:09:57 AM ERROR: bindsock' helper application is missing, not executable, not setuid root, or no sticky bit set 05/22/2012 01:09:57 AM SMTP Server: Listener failure: 'bindsock' is missing, not executable, not owned by root, not setuid root or user needs net_privaddr privilege. 05/22/2012 01:09:57 AM Suspending listen task for 20 seconds due to network errors
The settings for bindsock were correct (see IBM technote: http://www-01.ibm.com/support/docview.wss?uid=swg21097534)
$ ls -l /opt/lotus/notes/latest/ibmpow/bindsock
-r-sr-xr-x 1 root bin 14488 Jan 10 20:45 bindsock
which is correct.
It appeared sendmail was still running causing a port conflict. The solution is to stop sendmail and prevent it from starting again.
To stop sendmail from starting on reboot, comment it out in the /etc/rc.tcpip file. Then do stopsrc -s sendmail to end the running copy.