I have been trying to forward my email through Google Gmail to use their spam filter, but no matter what I do the Dreamhost SMTP server (Postfix) flags my messages as a mail loop.
What I'm doing is setting up a procmail recipe that forwards all incoming email to an account at Gmail.com. Before forwarding the message procmail uses formail to add an additional header to the message. Here's the recipe:
* ! ^X-Loop: joeuser@gmail\.com
| formail -A"X-Loop: email@example.com"
The account on Gmail is then set up to forward all non-spam back to my originating email account. When the email comes back, it is supposed to be delivered normally because the procmail recipe sees the added header and does nothing.
However, Postfix is too damn smart! It sees this as a mail loop and just sends an error message back to Gmail.
Is there any way to get this to work?