Virtualmin--> Servers->Dkim Errors on Ubuntu 18.04


I have Dkim installed and running.

But virtualmin module not open.

1st error is not found /etc/dkim-filter.conf

I create one simbolic link
#ln -s /etc/opendkim.conf /etc/dkim-filter.conf

now i still have this error

“DomainKeys indentified mail is not available on this system : The DKIM filter server boot script dkim-filter does not exist
However, Virtualmin can attempt to automatically install the DKIM filter package for you.”

 opendkim.service - OpenDKIM DomainKeys Identified Mail (DKIM) Milter
   Loaded: loaded (/lib/systemd/system/opendkim.service; enabled; vendor preset: enabled)
   Active: active (running) since Tue 2018-05-01 17:58:56 WEST; 1 day 3h ago
     Docs: man:opendkim(8)
 Main PID: 14739 (opendkim)
    Tasks: 7 (limit: 2310)
   CGroup: /system.slice/opendkim.service
           └─14739 /usr/sbin/opendkim -x /etc/opendkim.conf

I have all packages installed and running.

open dkim is running on socket 8891.

Any help?

If possible, use Ubuntu 16.04 before Virtualmin devs finish the huge work needed to support 18.04.

More details here: