On Fri, Feb 25, 2011 at 09:27:36AM +0100, martijn.list wrote: > > But is it possible? > > If the other MTAs are not under your control, you cannot enforce TLS > between the other MTAs. You can only enforce TLS between the MTA you > control and first MTA it connects to. After that you are no longer in > control.
The OP only wanted to use TLS when possible.
http://www.postfix.org/TLS_README.html#client_tls_may
--
Viktor.
