SOLVED
I found the solution

http://www.mail-archive.com/otrs@otrs.org/msg11385.html

thanks

On Fri, Feb 4, 2011 at 7:04 PM, Francesco Pasqualini <frapas@gmail.com> wrote:
Hi,
I put  the following line in Config.pm
$Self->{'PostmasterDefaultQueue'} = 'Raw';

But if I open a ticket by mail the ticket is created in the Postmaster queue instead of Raw.
What's the problem?

OTRS 3.0.5

Thanks