I am using Ubuntu 10.04 and by following this tutorial I have made RT run well in everything except for sending outbound emails. The difference is, I need to make RT use an external, existing mail server. The mail server is accessible via SMTP with authentication so I am looking for a place to insert the username and password, but nothing like that seems to exist.
The closest thing that I found by googling is that I need to setup ssmtp or msmtp and use it to forward my outbound emails to the mail server (sorry I lost the link). Is that true? Are there any (perhaps better) other ways?