[Mailman-Users] setup problems

[Renato César]

Hi, 


I have installed the mailman 2.1.9 following the site instructions, but the Postfix not recognize my list address. I use the "Integration with Postfix" describe in mailman site.
When I create a list by web interface the e-mails are sent normally, but when a member list send a message to list the Postfix returns the follow message : 

This is the Postfix program at host ns.sesa.com.br.

I'm sorry to have to inform you that your message could not
be delivered to one or more recipients. It's attached below.

For further assistance, please send mail to <postmaster>

If you do so, please include this problem report. You can
delete your own text from the attached returned message.

                   The Postfix program

list at teste.com: unknown user: list at teste.com


My Postfix is running with a MySQL database. 

thanks, 
Renato