I have a mail server with Postifx (and dovecot) setup, on which there is an alias address (say firstname.lastname@example.org) which forwards mail to my main email (email@example.com). This works fine, and all mail I send to firstname.lastname@example.org gets sent to email@example.com
However, when I reply to an email sent to firstname.lastname@example.org (using the gmail web interface), to the recipient, it looks like the mail came from email@example.com (or more specifically, the user of firstname.lastname@example.org, eg. Joe Bloggs).
Is there a way to make the email look like it came from email@example.com, or even just a custom name (such as Alias) rather than coming from Joe Bloggs < firstname.lastname@example.org >?