How do you configure a secondary smtp server in postfix using virtual mailboxes. I have that service through my dns provider. having some issues with yahoo mail and them blocking my server for some reason. Would also like to have a script that automatically redelivers using the secondary server in the event of an undeliverable return due to good ole yahoo or any other provider that would attempt redelivery 2 or 3 times before returning a undeliverable message to the user.
