Microsoft's own Exchange servers have Postfix on their spam filtering boxen front-end. Not exactly eating their own dog food, when they have their own Forefront Security for Exchange.
This is the Postfix program at host mailxxx-xxx-R.bigfish.com.
I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.
For further assistance, please send mail to
If you do so, please include this problem report. You can
delete your own text from the attached returned message.
The Postfix program
: host
xxxxx-xxxx-mail5.customer.frontbridge.com[131.107.115.214] said: 550 5.7.1
$whois frontbridge.com,
Domain Name: FRONTBRIDGE.COM
Registrar of Record: Corporate Domains, Inc.
Administrative Contact:
Microsoft Corporation
Domain Administrator
One Microsoft Way
Redmond, WA 98052
US
domains@microsoft.com
+1.4258828080 Fax: +1.4259367329
$whois bigfish.com ,
Domain Name: BIGFISH.COM
Registrar of Record: Corporate Domains, Inc.
Administrative Contact:
Microsoft Corporation
Domain Administrator
One Microsoft Way
Redmond, WA 98052
US
domains@microsoft.com
+1.4258828080 Fax: +1.4259367329