OK Resolved.
See link
http://kb.cf7skins.com/contact-form-7-email-issues/#mailserver
Basically, it says that you should put
Reply-To: [your-name] <[your-email]>
into the Additional Headers field. Altho the email will be FROM your domain email, the reply will go to the “senders” email.
I’ve tested it – it works!
