>> I get a "cannot test domains condition in EHLO or HELO ACL" error >> logged. Debug mode produces the following:
>
> Ah. Or does this mean exactly what it says, i.e. you can't
> use the "domains" condition in a HELO ACL?
Yes it means exactly that. Think about it a bit: How could you check
against a domain after HELO or EHLO? At that stage Exim has no
information about the sender or recipient and therefore cannot check
against it.