[rt-users] Sending welcome emails automatically to new users

[Subjected]

I'm trying to figure out how to send "welcome" emails to newly created 
RT users from new tickets. I know with incoming email, new tickets are 
being created just fine, but for each new user, I want to send them a 
"getting started" email with stuff like setting new password and howto's 
on using my support system.

We've been using RT for some time. The incoming email part works and 
creates new users as needed.

And I'm aware of this idea for auto-generating the self-service idea & 
new password and SendMail overlay for custom subject lines
http://requesttracker.wikia.com/wiki/AutogeneratedPassword
http://requesttracker.wikia.com/wiki/SendEmail

Using those 2 I can make a welcome email that sets a temporary password, 
along with howto instructions, and does not have the ticket# in the 
subject field. I also send the normal new ticket reply. So when I get a 
new user and their first request, it sends 2 emails, one for the 
new-ticket-created reply and another "welcome to the system." After 
that, only 1 email is sent back for each ticket.

I want to be able to do the same for requestors, cc's, etc, whether they 
exist at ticket creation or are later added.

Help?