title: how to getMailer in model class
body: <p>I want to set up a user login process on top of sfGuardDoctrine, which sets the password to a random one. This is happening when the user is created or when his password is reset.</p>
  
  <p>I figure I should centralise this routine in the sfGuardUser model class? What I can't figure out is how to get the Swiftmailer instance from there. All documentation seems to call it from within an action.</p>