Comment # 31 on bug 1092352 from Marius Tomaschewski

(In reply to Ludwig Nussel from comment #16)
[...]
> > Mai 14 07:56:03 linux-e202.suse.de dns-resolver[31222]: ATTENTION: You have
> > modified /etc/resolv.conf. Leaving it untouched...
> 
> That's what netconfig says if resolv.conf already was modified. We are
> currently looking for the point in time where NM decides to not use
> netconfig.

Exactly. Instead to write it directly (on code 20 or any another occasion)
call "netconfig update -f" when a netconfig call returns with code 20.