Hi,
I just wanted to announce that we recently shipped version 3 of Qurb
(pronounced 'Curb'), an anti-spam plug-in for Outlook and Outlook
Express that now includes support for SPF. Qurb is primarily a whitelist
based anti-spam solution and we use SPF to help users figure out where
an email really came from.
For messages that get an SPF PASS Qurb displays a small "Received From
<domain>" stamp on the message. For messages that get an SPF SOFT FAIL
or FAIL Qurb displays a "Not Verified <domain>" stamp. A screenshot of
what this looks like in the Outlook UI can be found here:
http://www.qurb.com/products/phishing.php
SPF is not perfect (as many posters to this list have pointed out) and
so Qurb will occasionally mark a legitimate message as "Not Verified"
because of forwarding, poorly configured SPF records, etc. However, Qurb
will never throw mail away because of a FAIL or SOFT FAIL and it will
not put the "Received From" stamp on a forged message. Even considering
SPF's limitations, especially in the context of an MUA implementation,
our experience with it has been great.
If you are doing SPF development and want to use Qurb beyond the 14 day
evaluation period, just send me a note and I can generate a license key
for you.
Thanks,
Linus