Jon

Couple of thoughts

Message Labs, Postini  are both pretty decent firms and I doubt they would develop a product with such an obvious flaw. This leads me to believe that they don't intend you to do mass mailings to B2C domains.

If this is true then your only option (other than employing the services of a company like Pure).....

Setup a new domain and mail sever without message labs on it, you can then apply domain keys, SPF, sender ID, feedback loops and all the other gubbins. Or if it is possible at your end create a subdomain of your main domain again with the same records.

Not exactly original thinking on my part but I hope it helps.

Marc
Pure
marc.munier@pure360.com

On 09:54:57 26 February 2008 JonBov wrote:

Hi

Companies like Messagelabs and Postini provide inbound and outbound mail filtering for spam, virus, archiving etc.

They do so by 'sitting in front of' your mail server in the form of MX records.

Meanwhile, companies like AOL filter spam aggressively by checking the apparent sender domain against the senders IP.

So if Im sending email from jon@company123.com
and the IP that appears when you lookup my IP - would normally resolve to mail.company123.com but instead resolves to cluster3.eu.messagelabs.com. or similar.

I recently had an experience where AOL blocked a domain, and refused to remove the block because the sending IP  did not belong to 'company123'... it belonged to (and resolved to!) messagelabs.

Surely I cannot be the only one in this boat with Messagelabs, Postini or any other number of mail filtering services?
I have correctly configured SPF 1&2, SenderID and Domainkeys.

When i spoke to Messagelabs - I did not get intelligent responses.
ie. Messagelabs had no clue.

It seems a fundamental problem and one that it not going to go away?

Any experiences here?

cheers
jon