Last updated: 19/01/2016
A well known problem when sending e-mails through webservers is the wrong From: address that by default points to the server's name. This can cause some problems: mails never arrive, replies are sent to a non active or not actively checked mailbox and bounces may arrive at the hosting company or worse disappear in the bitbucket.
In PHP it is relatively easy to fix:
<?php mail('email@example.com', 'subject', 'message', null, '-f firstname.lastname@example.org'); ?>
The last parameter ' -f ' allows you to specify the From: address for the sendmail function.