Sending eMail from internal host via 25 (unencrypted)

Hi there,

I know, it’s a bad idea, but I’m forced to do this in this specific setup.

There are running some specific systems, which can’t send Mails encrypted via SMTP (and it’s not cangeable). Is there any possibility to enable unencrypted usage of SMTP for internal (RFC1918) clients?

All the best, Tim