prevent procmail from adding Return-path

Hi,

I'm forwarding mails as a copy to another domain.

Sometimes I get an error message saying:

Mail rejected. DMARC check failed. OFR_515
[515] (in reply to end of DATA command)

I could imagine, that this is because procmail changes the return-path original to my server send path.
And dkim entry in the original mail is made for the original sender.

So I think if it would make sense to keep the original return-path in the forwarded mail.

How could I do this?

The forwarding code follows:

:0 c
* (^TO_|for.*)mail@mydomain.com
* !^X-Loop: mail@mydomain.com
* !^From mail@otherdomain.com
{
:0 hfw
* ^Subject:\/.+
| formail -I "Subject: FORWARDED:$MATCH"
:0 a
! mail@otherdomain.com
}

Thanks in advance for any tip.

Cheers mike