2009/12/4 Bret Clark <bclark@spectraaccess.com>
If the customer insist on using their domain, then you would have to have the customer setup an SPF record within their domain that points to your email server IP blocks. I would just tell your customer that if they insist of using their FROM domain, to help get past someone's spamming system the customer is going to have to add the a SPF record to their domain similar to the following:
[customer domain].com. IN TXT "v=spf1 a mx ip4:[your IP block]
Putting an SPF record in your DNS record will have no affect on spamming software. SPF is basically another form of reverse DNS at the mail level.
Bret
The problem we face is that some people we work with can't do that, they can't even grasp what an SPF record is and so as far as our own spam filtering goes, we have filtered their emails to us sent with the FROM address being an @mysurname.com domain which doesn't exist and as a result we have filtered out their mails so we have had to lower our SPF checking slightly which is so annoying :S -- Regards, James ;) Charles de Gaulle<http://www.brainyquote.com/quotes/authors/c/charles_de_gaulle.html> - "The better I get to know men, the more I find myself loving dogs."