On Fri, 2009-12-04 at 11:45 -0500, Jeffrey Negro wrote:
Thanks for your input on this. My main concern is mail filters at the end users side thinking that our mail servers are spoofing our customer's domain.
If you really feel that SPF is going to help, then keep all the mail in your domain's control by using VERP addresses as the envelope sender address (like most decent modern MLM packages do). That way you can have a "From: " header in the customer domain (or of your choosing), and the envelope sender in your own. The benefit here is that not only does it make the usage of SPF a lot less complex, but it also means that all bounces come back to the originating system and can be handled accordingly. Have a look at the headers of this message for a well-formed example. Of course, this does depend upon people believing that SPF is actually useful... Graeme