Comment 1 for bug 317563

It uses the specified email and owner variables for the From: header. However, the Envelope FROM in the SMTP session is decided by the Mail::Internet perl module that caff uses.

I think it should be possible to use the MailFrom option from this perl module to specify the envelope from.

It's a design decision from caff to make it agnostic of which email transport you use. Otherwise we would have to reimplement SMTP and sendmail and ... functionality in this script, and in the next script, etc. Adding such an option to caff is hence not 'simple' as it complicates the codebase, rather than abstracting the sending away to the tools that are good at sending email.