Looking at the guidance here:
http://www.virtualmin.com/documentation/email/dependent
it says that Postfix 2.7 is needed. I have an up to date WM and VM install, but it has 2.6.6 installed.
What should I do?
Paul
Howdy,
Yeah, with CentOS 6, the most recent version of Postfix they provide doesn’t support the Sender Dependent Outgoing IP Address feature.
Unfortunately, there isn’t a good solution.
The only two options are to use a third party repository to obtain a more recent Postfix version – but we don’t recommend using packages from third party repositories – or you could try a different Linux distribution, but that’s obviously quite a bit of work to change 
The next CentOS version will have a more recent Postfix version, but likely some time off still.
Sorry, I wish there were a better solution
-Eric
Eric,
thanks for the update.
Is it worth putting a comment on that advice page, to update people at that stage?
Paul