I'm looking at adding some postfix config enhancements and had some questions: Is there a minimum supported version of postfix in ispconfig? Is there a standard/preferred method to handle version-specific settings? Eg. could test postconf -d mail_version output and write version-dependent configuation. Or could put a checkbox/handle in the UI and let administrators turn things on if they want (and presumably know what they're doing). Is this done anywhere already as an example? Is there a reason the submission service (port 587) isn't setup by default? Is there any opposition to doing so? Same for smtps on 465? I wouldn't mind seeing a checkbox on this one and defaulting to disabled, as I believe smtps is deprecated in favor of submission+STARTTLS. You do still run into old mail clients that require it now and then (eg. I think our office copier supports smtps but not starttls), so it probably is needed in some places.