title: How do I "send" emails to the Sent Folder
body: <p>We provide a web service that can email invoices and statements from our servers to our users customers. 
  Our users have asked us that all emails sent from the web-service are also stored in the Sent Folder of the person using the web service. </p>
  
  <p>We know the users email, and we could insist they provide us with IMAP access credentials. </p>
  
  <p>What options do we have for saving emails sent by a user from our server in the Sent Mail folder of that user?</p>
  
  <p>(hope that makes sense. It was pretty hard to explain)</p>