[Dovecot] Duplicate supression mechanism

Hello,

In a Dovecot 2.0.6 server I have an account x@domain and an alias y@domain -> x@domain.

When I send an email to x@domain with carbon copy to y@domain, X receives two messages on mailbox. Dovecot2 has any feature of duplicate suppression ?

Thanks

Thiago Henrique adminlinux.com.br