In order to use an email alias as a distribution list you first need to create the e-mail address within the Customer Control Panel
> Mail Tab > Add New Mailbox.
Enter the Display name, login, and password for the e-mail address > Click Next
Uncheck (disable) Storage
Enable Mail Forwarding and then enter all of the e-mail addresses you want the “list” to forward to. > Click Next
Click Finish, you’re done!