[rt-users] Filter mails from outside my own domain

[Matias]

Hi,

I have a new RT installation (latest version) and I need to NOT 
autoreply mails coming from outside my domain, lets say @example.com.


So, any internal user sending a mail to helpdesk at example.com should get 
an autoreply and any user sending a mail from anything else should get 
nothing.

Any suggestion?


Thanks